920647639 has 4 divisors (see below), whose sum is σ = 920910024. Its totient is φ = 920385256.

The previous prime is 920647627. The next prime is 920647667. The reversal of 920647639 is 936746029.

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 920647639 - 2²³ = 912259031 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 (920647619) 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, 125857 + ... + 132970.

It is an arithmetic number, because the mean of its divisors is an integer number (230227506).

Almost surely, 2^920647639 is an apocalyptic number.

920647639 is a deficient number, since it is larger than the sum of its proper divisors (262385).

920647639 is a wasteful number, since it uses less digits than its factorization.

920647639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262384.

The product of its (nonzero) digits is 489888, while the sum is 46.

The square root of 920647639 is about 30342.1759107682. The cubic root of 920647639 is about 972.8169924176.

The spelling of 920647639 in words is "nine hundred twenty million, six hundred forty-seven thousand, six hundred thirty-nine".