213251965 has 8 divisors (see below), whose sum is σ = 256028760. Its totient is φ = 170517312.

The previous prime is 213251957. The next prime is 213251977. The reversal of 213251965 is 569152312.

It can be written as a sum of positive squares in 4 ways, for example, as 9504889 + 203747076 = 3083^2 + 14274^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 213251965 - 2³ = 213251957 is a prime.

It is a super-2 number, since 2×213251965² = 90952801152722450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 213251965.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1947 + ... + 20743.

It is an arithmetic number, because the mean of its divisors is an integer number (32003595).

Almost surely, 2^213251965 is an apocalyptic number.

It is an amenable number.

213251965 is a deficient number, since it is larger than the sum of its proper divisors (42776795).

213251965 is a wasteful number, since it uses less digits than its factorization.

213251965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21071.

The product of its digits is 16200, while the sum is 34.

The square root of 213251965 is about 14603.1491466738. The cubic root of 213251965 is about 597.4446556232. Note that the first 3 decimals are identical.

The spelling of 213251965 in words is "two hundred thirteen million, two hundred fifty-one thousand, nine hundred sixty-five".