21311102997 has 20 divisors (see below), whose sum is σ = 31975374816. Its totient is φ = 14144802120.

The previous prime is 21311102987. The next prime is 21311103053. The reversal of 21311102997 is 79920111312.

It is not a de Polignac number, because 21311102997 - 2⁸ = 21311102741 is a prime.

It is a super-2 number, since 2×21311102997² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311102977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 561129 + ... + 597902.

Almost surely, 2^21311102997 is an apocalyptic number.

21311102997 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21311102997 is a deficient number, since it is larger than the sum of its proper divisors (10664271819).

21311102997 is a wasteful number, since it uses less digits than its factorization.

21311102997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1159270 (or 1159261 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 36.

The spelling of 21311102997 in words is "twenty-one billion, three hundred eleven million, one hundred two thousand, nine hundred ninety-seven".