21156071323 has 8 divisors (see below), whose sum is σ = 21243942720. Its totient is φ = 21068378760.

The previous prime is 21156071317. The next prime is 21156071327. The reversal of 21156071323 is 32317065112.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21156071323 is a prime.

It is a super-3 number, since 3×21156071323³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21156071327) 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, 195036 + ... + 283462.

It is an arithmetic number, because the mean of its divisors is an integer number (2655492840).

Almost surely, 2^21156071323 is an apocalyptic number.

21156071323 is a deficient number, since it is larger than the sum of its proper divisors (87871397).

21156071323 is an equidigital number, since it uses as much as digits as its factorization.

21156071323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89417.

The product of its (nonzero) digits is 7560, while the sum is 31.

The spelling of 21156071323 in words is "twenty-one billion, one hundred fifty-six million, seventy-one thousand, three hundred twenty-three".