213772931 has 4 divisors (see below), whose sum is σ = 220668864. Its totient is φ = 206877000.

The previous prime is 213772921. The next prime is 213772957. The reversal of 213772931 is 139277312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 213772931 - 2¹⁴ = 213756547 is a prime.

It is a super-2 number, since 2×213772931² = 91397732056661522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213772891 and 213772900.

It is not an unprimeable number, because it can be changed into a prime (213772921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3447920 + ... + 3447981.

It is an arithmetic number, because the mean of its divisors is an integer number (55167216).

Almost surely, 2^213772931 is an apocalyptic number.

213772931 is a deficient number, since it is larger than the sum of its proper divisors (6895933).

213772931 is an equidigital number, since it uses as much as digits as its factorization.

213772931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6895932.

The product of its digits is 15876, while the sum is 35.

The square root of 213772931 is about 14620.9757198348. The cubic root of 213772931 is about 597.9307710972.

The spelling of 213772931 in words is "two hundred thirteen million, seven hundred seventy-two thousand, nine hundred thirty-one".