221025413 has 4 divisors (see below), whose sum is σ = 252600480. Its totient is φ = 189450348.

The previous prime is 221025403. The next prime is 221025419. The reversal of 221025413 is 314520122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221025413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221025419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15787523 + ... + 15787536.

It is an arithmetic number, because the mean of its divisors is an integer number (63150120).

Almost surely, 2^221025413 is an apocalyptic number.

It is an amenable number.

221025413 is a deficient number, since it is larger than the sum of its proper divisors (31575067).

221025413 is an equidigital number, since it uses as much as digits as its factorization.

221025413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31575066.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 221025413 is about 14866.9234544340. The cubic root of 221025413 is about 604.6175330063.

Adding to 221025413 its reverse (314520122), we get a palindrome (535545535).

The spelling of 221025413 in words is "two hundred twenty-one million, twenty-five thousand, four hundred thirteen".