21455855412 has 48 divisors (see below), whose sum is σ = 53220417600. Its totient is φ = 6708441600.

The previous prime is 21455855381. The next prime is 21455855423.

21455855412 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 442837 + ... + 488892.

It is an arithmetic number, because the mean of its divisors is an integer number (1108758700).

Almost surely, 2^21455855412 is an apocalyptic number.

It is an amenable number.

21455855412 is an abundant number, since it is smaller than the sum of its proper divisors (31764562188).

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

21455855412 is a wasteful number, since it uses less digits than its factorization.

21455855412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 931856 (or 931854 counting only the distinct ones).

The product of its digits is 320000, while the sum is 42.

The spelling of 21455855412 in words is "twenty-one billion, four hundred fifty-five million, eight hundred fifty-five thousand, four hundred twelve".