21229167856 has 40 divisors (see below), whose sum is σ = 46626824720. Its totient is φ = 9282387456.

The previous prime is 21229167853. The next prime is 21229167857. The reversal of 21229167856 is 65876192212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21229167851) 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, 2681925 + ... + 2689828.

It is an arithmetic number, because the mean of its divisors is an integer number (1165670618).

Almost surely, 2^21229167856 is an apocalyptic number.

21229167856 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21229167856 is an abundant number, since it is smaller than the sum of its proper divisors (25397656864).

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

21229167856 is a wasteful number, since it uses less digits than its factorization.

21229167856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5371793 (or 5371787 counting only the distinct ones).

The product of its digits is 725760, while the sum is 49.

The spelling of 21229167856 in words is "twenty-one billion, two hundred twenty-nine million, one hundred sixty-seven thousand, eight hundred fifty-six".