216461631 has 8 divisors (see below), whose sum is σ = 288820224. Its totient is φ = 144205400.

The previous prime is 216461627. The next prime is 216461633. The reversal of 216461631 is 136164612.

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 216461631 - 2² = 216461627 is a prime.

It is a super-2 number, since 2×216461631² = 93711275390360322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216461633) 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, 20511 + ... + 29216.

It is an arithmetic number, because the mean of its divisors is an integer number (36102528).

Almost surely, 2^216461631 is an apocalyptic number.

216461631 is a deficient number, since it is larger than the sum of its proper divisors (72358593).

216461631 is a wasteful number, since it uses less digits than its factorization.

216461631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51181.

The product of its digits is 5184, while the sum is 30.

The square root of 216461631 is about 14712.6350800936. The cubic root of 216461631 is about 600.4271319694.

The spelling of 216461631 in words is "two hundred sixteen million, four hundred sixty-one thousand, six hundred thirty-one".