21478596931 has 16 divisors (see below), whose sum is σ = 23568485760. Its totient is φ = 19411729920.

The previous prime is 21478596929. The next prime is 21478596959. The reversal of 21478596931 is 13969587412.

It is a happy number.

It is not a de Polignac number, because 21478596931 - 2¹ = 21478596929 is a prime.

It is a super-2 number, since 2×21478596931² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21478596961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4623696 + ... + 4628338.

It is an arithmetic number, because the mean of its divisors is an integer number (1473030360).

Almost surely, 2^21478596931 is an apocalyptic number.

21478596931 is a deficient number, since it is larger than the sum of its proper divisors (2089888829).

21478596931 is a wasteful number, since it uses less digits than its factorization.

21478596931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7026.

The product of its digits is 3265920, while the sum is 55.

The spelling of 21478596931 in words is "twenty-one billion, four hundred seventy-eight million, five hundred ninety-six thousand, nine hundred thirty-one".