16651651615 has 4 divisors (see below), whose sum is σ = 19981981944. Its totient is φ = 13321321288.

The previous prime is 16651651579. The next prime is 16651651631. The reversal of 16651651615 is 51615615661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16651651615 - 2²⁵ = 16618097183 is a prime.

It is a super-3 number, since 3×16651651615³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1665165157 + ... + 1665165166.

It is an arithmetic number, because the mean of its divisors is an integer number (4995495486).

Almost surely, 2^16651651615 is an apocalyptic number.

16651651615 is a deficient number, since it is larger than the sum of its proper divisors (3330330329).

16651651615 is an equidigital number, since it uses as much as digits as its factorization.

16651651615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3330330328.

The product of its digits is 162000, while the sum is 43.

The spelling of 16651651615 in words is "sixteen billion, six hundred fifty-one million, six hundred fifty-one thousand, six hundred fifteen".