21130319997 has 12 divisors (see below), whose sum is σ = 30528165564. Its totient is φ = 14083837440.

The previous prime is 21130319953. The next prime is 21130320007. The reversal of 21130319997 is 79991303112.

21130319997 is a `hidden beast` number, since 211 + 30 + 319 + 9 + 97 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 13656025881 + 7474294116 = 116859^2 + 86454^2 .

It is not a de Polignac number, because 21130319997 - 2¹⁰ = 21130318973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130319897) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 209154 + ... + 293267.

It is an arithmetic number, because the mean of its divisors is an integer number (2544013797).

Almost surely, 2^21130319997 is an apocalyptic number.

It is an amenable number.

21130319997 is a deficient number, since it is larger than the sum of its proper divisors (9397845567).

21130319997 is a wasteful number, since it uses less digits than its factorization.

21130319997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507100 (or 507097 counting only the distinct ones).

The product of its (nonzero) digits is 91854, while the sum is 45.

The spelling of 21130319997 in words is "twenty-one billion, one hundred thirty million, three hundred nineteen thousand, nine hundred ninety-seven".