77970 has 32 divisors (see below), whose sum is σ = 196992. Its totient is φ = 19712.

The previous prime is 77969. The next prime is 77977. The reversal of 77970 is 7977.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (77977) 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, 634 + ... + 746.

It is an arithmetic number, because the mean of its divisors is an integer number (6156).

2⁷⁷⁹⁷⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77970, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98496).

77970 is an abundant number, since it is smaller than the sum of its proper divisors (119022).

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

77970 is a wasteful number, since it uses less digits than its factorization.

77970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146.

The product of its (nonzero) digits is 3087, while the sum is 30.

The square root of 77970 is about 279.2310870945. The cubic root of 77970 is about 42.7211083470.

The spelling of 77970 in words is "seventy-seven thousand, nine hundred seventy".