21122993997 has 16 divisors (see below), whose sum is σ = 35763799680. Its totient is φ = 12070282176.

The previous prime is 21122993977. The next prime is 21122994007. The reversal of 21122993997 is 79939922112.

21122993997 is a `hidden beast` number, since 21 + 1 + 229 + 9 + 399 + 7 = 666.

It is not a de Polignac number, because 21122993997 - 2⁸ = 21122993741 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122993977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55880748 + ... + 55881125.

It is an arithmetic number, because the mean of its divisors is an integer number (2235237480).

Almost surely, 2^21122993997 is an apocalyptic number.

21122993997 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21122993997 is a deficient number, since it is larger than the sum of its proper divisors (14640805683).

21122993997 is a wasteful number, since it uses less digits than its factorization.

21122993997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111761889 (or 111761883 counting only the distinct ones).

The product of its digits is 1102248, while the sum is 54.

The spelling of 21122993997 in words is "twenty-one billion, one hundred twenty-two million, nine hundred ninety-three thousand, nine hundred ninety-seven".