78811980 has 96 divisors (see below), whose sum is σ = 240844800. Its totient is φ = 19139328.

The previous prime is 78811979. The next prime is 78811987. The reversal of 78811980 is 8911887.

It is a super-2 number, since 2×78811980² = 12422656383040800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78811987) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60981 + ... + 62259.

It is an arithmetic number, because the mean of its divisors is an integer number (2508800).

Almost surely, 2^78811980 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78811980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120422400).

78811980 is an abundant number, since it is smaller than the sum of its proper divisors (162032820).

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

78811980 is a wasteful number, since it uses less digits than its factorization.

78811980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1383 (or 1381 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 42.

The square root of 78811980 is about 8877.6111651728. The cubic root of 78811980 is about 428.7433656151.

The spelling of 78811980 in words is "seventy-eight million, eight hundred eleven thousand, nine hundred eighty".