216651701 has 4 divisors (see below), whose sum is σ = 247601952. Its totient is φ = 185701452.

The previous prime is 216651691. The next prime is 216651707. The reversal of 216651701 is 107156612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 216651701 - 2⁶ = 216651637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216651707) 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, 15475115 + ... + 15475128.

It is an arithmetic number, because the mean of its divisors is an integer number (61900488).

Almost surely, 2^216651701 is an apocalyptic number.

It is an amenable number.

216651701 is a deficient number, since it is larger than the sum of its proper divisors (30950251).

216651701 is an equidigital number, since it uses as much as digits as its factorization.

216651701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30950250.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 216651701 is about 14719.0930766810. The cubic root of 216651701 is about 600.6028209938.

The spelling of 216651701 in words is "two hundred sixteen million, six hundred fifty-one thousand, seven hundred one".