213661371465 has 24 divisors (see below), whose sum is σ = 370429338240. Its totient is φ = 113927205024.

The previous prime is 213661371449. The next prime is 213661371467. The reversal of 213661371465 is 564173166312.

213661371465 is a `hidden beast` number, since 2 + 13 + 6 + 613 + 7 + 14 + 6 + 5 = 666.

It is not a de Polignac number, because 213661371465 - 2⁴ = 213661371449 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 213661371465.

It is not an unprimeable number, because it can be changed into a prime (213661371467) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 327825 + ... + 731294.

It is an arithmetic number, because the mean of its divisors is an integer number (15434555760).

Almost surely, 2^213661371465 is an apocalyptic number.

It is an amenable number.

213661371465 is a deficient number, since it is larger than the sum of its proper divisors (156767966775).

213661371465 is a wasteful number, since it uses less digits than its factorization.

213661371465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1063613 (or 1063610 counting only the distinct ones).

The product of its digits is 544320, while the sum is 45.

The spelling of 213661371465 in words is "two hundred thirteen billion, six hundred sixty-one million, three hundred seventy-one thousand, four hundred sixty-five".