216640028757 has 4 divisors (see below), whose sum is σ = 288853371680. Its totient is φ = 144426685836.

The previous prime is 216640028743. The next prime is 216640028797. The reversal of 216640028757 is 757820046612.

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 not a de Polignac number, because 216640028757 - 2¹⁸ = 216639766613 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 (216640028797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36106671457 + ... + 36106671462.

It is an arithmetic number, because the mean of its divisors is an integer number (72213342920).

Almost surely, 2^216640028757 is an apocalyptic number.

It is an amenable number.

216640028757 is a deficient number, since it is larger than the sum of its proper divisors (72213342923).

216640028757 is an equidigital number, since it uses as much as digits as its factorization.

216640028757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72213342922.

The product of its (nonzero) digits is 1128960, while the sum is 48.

The spelling of 216640028757 in words is "two hundred sixteen billion, six hundred forty million, twenty-eight thousand, seven hundred fifty-seven".