21229257084 has 48 divisors (see below), whose sum is σ = 56680490496. Its totient is φ = 6058094400.

The previous prime is 21229256987. The next prime is 21229257089. The reversal of 21229257084 is 48075292212.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21229257089) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84952 + ... + 222879.

It is an arithmetic number, because the mean of its divisors is an integer number (1180843552).

Almost surely, 2^21229257084 is an apocalyptic number.

It is an amenable number.

21229257084 is an abundant number, since it is smaller than the sum of its proper divisors (35451233412).

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

21229257084 is a wasteful number, since it uses less digits than its factorization.

21229257084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308666 (or 308664 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 42.

The spelling of 21229257084 in words is "twenty-one billion, two hundred twenty-nine million, two hundred fifty-seven thousand, eighty-four".