656139228 has 24 divisors (see below), whose sum is σ = 1546152720. Its totient is φ = 216547200.

The previous prime is 656139109. The next prime is 656139229. The reversal of 656139228 is 822931656.

It is a self number, because there is not a number n which added to its sum of digits gives 656139228.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656139229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269473 + ... + 271896.

It is an arithmetic number, because the mean of its divisors is an integer number (64423030).

Almost surely, 2^656139228 is an apocalyptic number.

It is an amenable number.

656139228 is an abundant number, since it is smaller than the sum of its proper divisors (890013492).

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

656139228 is a wasteful number, since it uses less digits than its factorization.

656139228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541477 (or 541475 counting only the distinct ones).

The product of its digits is 155520, while the sum is 42.

The square root of 656139228 is about 25615.2147755977. The cubic root of 656139228 is about 868.9577636863.

The spelling of 656139228 in words is "six hundred fifty-six million, one hundred thirty-nine thousand, two hundred twenty-eight".