212665631 has 8 divisors (see below), whose sum is σ = 226171440. Its totient is φ = 199270528.

The previous prime is 212665601. The next prime is 212665643. The reversal of 212665631 is 136566212.

212665631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 212665631 - 2¹⁸ = 212403487 is a prime.

It is a super-2 number, since 2×212665631² = 90453341217256322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212665601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23696 + ... + 31413.

It is an arithmetic number, because the mean of its divisors is an integer number (28271430).

Almost surely, 2^212665631 is an apocalyptic number.

212665631 is a deficient number, since it is larger than the sum of its proper divisors (13505809).

212665631 is a wasteful number, since it uses less digits than its factorization.

212665631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55353.

The product of its digits is 12960, while the sum is 32.

The square root of 212665631 is about 14583.0597269572. The cubic root of 212665631 is about 596.8965971225.

The spelling of 212665631 in words is "two hundred twelve million, six hundred sixty-five thousand, six hundred thirty-one".