77121792 has 216 divisors, whose sum is σ = 258279840. Its totient is φ = 21872640.

The previous prime is 77121773. The next prime is 77121797. The reversal of 77121792 is 29712177.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (77121797) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 430759 + ... + 430937.

It is an arithmetic number, because the mean of its divisors is an integer number (1195740).

Almost surely, 2^77121792 is an apocalyptic number.

77121792 is a gapful number since it is divisible by the number (72) 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 77121792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129139920).

77121792 is an abundant number, since it is smaller than the sum of its proper divisors (181158048).

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

77121792 is a wasteful number, since it uses less digits than its factorization.

77121792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 212 counting only the distinct ones).

The product of its digits is 12348, while the sum is 36.

The square root of 77121792 is about 8781.9013886515. The cubic root of 77121792 is about 425.6562723566.

The spelling of 77121792 in words is "seventy-seven million, one hundred twenty-one thousand, seven hundred ninety-two".