21797315892 has 48 divisors (see below), whose sum is σ = 61648977600. Its totient is φ = 6605246880.

The previous prime is 21797315873. The next prime is 21797315921. The reversal of 21797315892 is 29851379712.

It is a happy number.

21797315892 is a `hidden beast` number, since 21 + 7 + 9 + 7 + 31 + 589 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9172767 + ... + 9175142.

It is an arithmetic number, because the mean of its divisors is an integer number (1284353700).

Almost surely, 2^21797315892 is an apocalyptic number.

21797315892 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21797315892 is an abundant number, since it is smaller than the sum of its proper divisors (39851661708).

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

21797315892 is a wasteful number, since it uses less digits than its factorization.

21797315892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18347933 (or 18347925 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 54.

The spelling of 21797315892 in words is "twenty-one billion, seven hundred ninety-seven million, three hundred fifteen thousand, eight hundred ninety-two".