77791420 has 36 divisors (see below), whose sum is σ = 190035720. Its totient is φ = 26671008.

The previous prime is 77791411. The next prime is 77791421. The reversal of 77791420 is 2419777.

It is a self number, because there is not a number n which added to its sum of digits gives 77791420.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77791421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38710 + ... + 40669.

It is an arithmetic number, because the mean of its divisors is an integer number (5278770).

Almost surely, 2^77791420 is an apocalyptic number.

77791420 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

77791420 is an abundant number, since it is smaller than the sum of its proper divisors (112244300).

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

77791420 is a wasteful number, since it uses less digits than its factorization.

77791420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79402 (or 79393 counting only the distinct ones).

The product of its (nonzero) digits is 24696, while the sum is 37.

The square root of 77791420 is about 8819.9444442695. The cubic root of 77791420 is about 426.8846772685.

The spelling of 77791420 in words is "seventy-seven million, seven hundred ninety-one thousand, four hundred twenty".