221020025 has 12 divisors (see below), whose sum is σ = 274443372. Its totient is φ = 176571840.

The previous prime is 221020003. The next prime is 221020039. The reversal of 221020025 is 520020122.

It can be written as a sum of positive squares in 6 ways, for example, as 52954729 + 168065296 = 7277^2 + 12964^2 .

It is not a de Polignac number, because 221020025 - 2⁶ = 221019961 is a prime.

It is a super-3 number, since 3×221020025³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221019991 and 221020009.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13607 + ... + 25043.

It is an arithmetic number, because the mean of its divisors is an integer number (22870281).

Almost surely, 2^221020025 is an apocalyptic number.

221020025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221020025 is a deficient number, since it is larger than the sum of its proper divisors (53423347).

221020025 is a wasteful number, since it uses less digits than its factorization.

221020025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12220 (or 12215 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 221020025 is about 14866.7422456973. The cubic root of 221020025 is about 604.6126199880.

Adding to 221020025 its reverse (520020122), we get a palindrome (741040147).

The spelling of 221020025 in words is "two hundred twenty-one million, twenty thousand, twenty-five".