997566879 has 16 divisors (see below), whose sum is σ = 1425434112. Its totient is φ = 618935328.

The previous prime is 997566877. The next prime is 997566893. The reversal of 997566879 is 978665799.

It is not a de Polignac number, because 997566879 - 2¹ = 997566877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997566877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 192819 + ... + 197924.

It is an arithmetic number, because the mean of its divisors is an integer number (89089632).

Almost surely, 2^997566879 is an apocalyptic number.

997566879 is a deficient number, since it is larger than the sum of its proper divisors (427867233).

997566879 is a wasteful number, since it uses less digits than its factorization.

997566879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390806.

The product of its digits is 51438240, while the sum is 66.

The square root of 997566879 is about 31584.2821510953. The cubic root of 997566879 is about 999.1883009896.

The spelling of 997566879 in words is "nine hundred ninety-seven million, five hundred sixty-six thousand, eight hundred seventy-nine".