77947940 has 96 divisors (see below), whose sum is σ = 196922880. Its totient is φ = 25353216.

The previous prime is 77947927. The next prime is 77947951. The reversal of 77947940 is 4974977.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 296249 + ... + 296511.

It is an arithmetic number, because the mean of its divisors is an integer number (2051280).

Almost surely, 2^77947940 is an apocalyptic number.

77947940 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77947940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98461440).

77947940 is an abundant number, since it is smaller than the sum of its proper divisors (118974940).

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

77947940 is a wasteful number, since it uses less digits than its factorization.

77947940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 379 counting only the distinct ones).

The product of its (nonzero) digits is 444528, while the sum is 47.

The square root of 77947940 is about 8828.8130572575. The cubic root of 77947940 is about 427.1707894876.

It can be divided in two parts, 77947 and 940, that added together give a palindrome (78887).

The spelling of 77947940 in words is "seventy-seven million, nine hundred forty-seven thousand, nine hundred forty".