77870947 has 16 divisors (see below), whose sum is σ = 99072000. Its totient is φ = 60675720.

The previous prime is 77870941. The next prime is 77870971. The reversal of 77870947 is 74907877.

It is not a de Polignac number, because 77870947 - 2²³ = 69482339 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77870947.

It is not an unprimeable number, because it can be changed into a prime (77870941) 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 15 ways as a sum of consecutive naturals, for example, 6547 + ... + 14092.

It is an arithmetic number, because the mean of its divisors is an integer number (6192000).

Almost surely, 2^77870947 is an apocalyptic number.

77870947 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

77870947 is a deficient number, since it is larger than the sum of its proper divisors (21201053).

77870947 is a wasteful number, since it uses less digits than its factorization.

77870947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20671 (or 20657 counting only the distinct ones).

The product of its (nonzero) digits is 691488, while the sum is 49.

The square root of 77870947 is about 8824.4516543522. The cubic root of 77870947 is about 427.0300973142.

The spelling of 77870947 in words is "seventy-seven million, eight hundred seventy thousand, nine hundred forty-seven".