221525125 has 8 divisors (see below), whose sum is σ = 276463512. Its totient is φ = 177220000.

The previous prime is 221525119. The next prime is 221525131. The reversal of 221525125 is 521525122.

It is an interprime number because it is at equal distance from previous prime (221525119) and next prime (221525131).

It can be written as a sum of positive squares in 4 ways, for example, as 63218401 + 158306724 = 7951^2 + 12582^2 .

It is not a de Polignac number, because 221525125 - 2¹⁵ = 221492357 is a prime.

It is a super-4 number, since 4×221525125⁴ (a number of 34 digits) contains 4444 as substring.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221525125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 885976 + ... + 886225.

It is an arithmetic number, because the mean of its divisors is an integer number (34557939).

Almost surely, 2^221525125 is an apocalyptic number.

221525125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221525125 is a deficient number, since it is larger than the sum of its proper divisors (54938387).

221525125 is an equidigital number, since it uses as much as digits as its factorization.

221525125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1772216 (or 1772206 counting only the distinct ones).

The product of its digits is 2000, while the sum is 25.

The square root of 221525125 is about 14883.7201330850. The cubic root of 221525125 is about 605.0728459971.

The spelling of 221525125 in words is "two hundred twenty-one million, five hundred twenty-five thousand, one hundred twenty-five".