79987770 has 32 divisors (see below), whose sum is σ = 213301440. Its totient is φ = 21330000.

The previous prime is 79987769. The next prime is 79987793. The reversal of 79987770 is 7778997.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 147856 + ... + 148395.

It is an arithmetic number, because the mean of its divisors is an integer number (6665670).

Almost surely, 2^79987770 is an apocalyptic number.

79987770 is an abundant number, since it is smaller than the sum of its proper divisors (133313670).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

79987770 is a wasteful number, since it uses less digits than its factorization.

79987770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296267 (or 296261 counting only the distinct ones).

The product of its (nonzero) digits is 1555848, while the sum is 54.

The square root of 79987770 is about 8943.5882060837. The cubic root of 79987770 is about 430.8649796072.

The spelling of 79987770 in words is "seventy-nine million, nine hundred eighty-seven thousand, seven hundred seventy".