655885640 has 16 divisors (see below), whose sum is σ = 1475742780. Its totient is φ = 262354240.

The previous prime is 655885621. The next prime is 655885673. The reversal of 655885640 is 46588556.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 563302756 + 92582884 = 23734^2 + 9622^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8198531 + ... + 8198610.

Almost surely, 2^655885640 is an apocalyptic number.

It is an amenable number.

655885640 is an abundant number, since it is smaller than the sum of its proper divisors (819857140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

655885640 is a wasteful number, since it uses less digits than its factorization.

655885640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16397152 (or 16397148 counting only the distinct ones).

The product of its (nonzero) digits is 1152000, while the sum is 47.

The square root of 655885640 is about 25610.2643484990. The cubic root of 655885640 is about 868.8458028675.

The spelling of 655885640 in words is "six hundred fifty-five million, eight hundred eighty-five thousand, six hundred forty".