77421960 has 512 divisors, whose sum is σ = 345600000. Its totient is φ = 15240960.

The previous prime is 77421947. The next prime is 77421977. The reversal of 77421960 is 6912477.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4074831 + ... + 4074849.

It is an arithmetic number, because the mean of its divisors is an integer number (675000).

Almost surely, 2^77421960 is an apocalyptic number.

77421960 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 77421960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (172800000).

77421960 is an abundant number, since it is smaller than the sum of its proper divisors (268178040).

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

77421960 is a wasteful number, since it uses less digits than its factorization.

77421960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 77421960 is about 8798.9749402984. The cubic root of 77421960 is about 426.2077938849.

The spelling of 77421960 in words is "seventy-seven million, four hundred twenty-one thousand, nine hundred sixty".