655425521 has 4 divisors (see below), whose sum is σ = 659824500. Its totient is φ = 651026544.

The previous prime is 655425493. The next prime is 655425527. The reversal of 655425521 is 125524556.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 122323600 + 533101921 = 11060^2 + 23089^2 .

It is a cyclic number.

It is not a de Polignac number, because 655425521 - 2¹⁴ = 655409137 is a prime.

It is a super-2 number, since 2×655425521² = 859165227156242882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (655425527) 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, 2199266 + ... + 2199563.

It is an arithmetic number, because the mean of its divisors is an integer number (164956125).

Almost surely, 2^655425521 is an apocalyptic number.

It is an amenable number.

655425521 is a deficient number, since it is larger than the sum of its proper divisors (4398979).

655425521 is a wasteful number, since it uses less digits than its factorization.

655425521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4398978.

The product of its digits is 60000, while the sum is 35.

The square root of 655425521 is about 25601.2796750475. The cubic root of 655425521 is about 868.6425835067.

The spelling of 655425521 in words is "six hundred fifty-five million, four hundred twenty-five thousand, five hundred twenty-one".