421553641656 has 48 divisors (see below), whose sum is σ = 1225946818440. Its totient is φ = 120443897280.

The previous prime is 421553641631. The next prime is 421553641673. The reversal of 421553641656 is 656146355124.

It is a happy number.

It is a congruent number.

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, 179230815 + ... + 179233166.

Almost surely, 2^421553641656 is an apocalyptic number.

It is an amenable number.

421553641656 is an abundant number, since it is smaller than the sum of its proper divisors (804393176784).

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

421553641656 is a wasteful number, since it uses less digits than its factorization.

421553641656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358464004 (or 358463993 counting only the distinct ones).

The product of its digits is 2592000, while the sum is 48.

The spelling of 421553641656 in words is "four hundred twenty-one billion, five hundred fifty-three million, six hundred forty-one thousand, six hundred fifty-six".