21529778297 has 8 divisors (see below), whose sum is σ = 21612729600. Its totient is φ = 21446910864.

The previous prime is 21529778273. The next prime is 21529778339. The reversal of 21529778297 is 79287792512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21529778297 - 2²⁶ = 21462669433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21529478297) 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, 520079 + ... + 559947.

It is an arithmetic number, because the mean of its divisors is an integer number (2701591200).

Almost surely, 2^21529778297 is an apocalyptic number.

It is an amenable number.

21529778297 is a deficient number, since it is larger than the sum of its proper divisors (82951303).

21529778297 is a wasteful number, since it uses less digits than its factorization.

21529778297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41935.

The product of its digits is 8890560, while the sum is 59.

The spelling of 21529778297 in words is "twenty-one billion, five hundred twenty-nine million, seven hundred seventy-eight thousand, two hundred ninety-seven".