21464165985 has 16 divisors (see below), whose sum is σ = 34345909440. Its totient is φ = 11446473920.

The previous prime is 21464165971. The next prime is 21464166019. The reversal of 21464165985 is 58956146412.

It is not a de Polignac number, because 21464165985 - 2⁴ = 21464165969 is a prime.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111895 + ... + 235475.

It is an arithmetic number, because the mean of its divisors is an integer number (2146619340).

Almost surely, 2^21464165985 is an apocalyptic number.

It is an amenable number.

21464165985 is a deficient number, since it is larger than the sum of its proper divisors (12881743455).

21464165985 is a wasteful number, since it uses less digits than its factorization.

21464165985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135168.

The product of its digits is 2073600, while the sum is 51.

The spelling of 21464165985 in words is "twenty-one billion, four hundred sixty-four million, one hundred sixty-five thousand, nine hundred eighty-five".