77893921 has 12 divisors (see below), whose sum is σ = 90213312. Its totient is φ = 65884104.

The previous prime is 77893919. The next prime is 77893931. The reversal of 77893921 is 12939877.

It is a happy number.

77893921 is a nontrivial binomial coefficient, being equal to C(12482, 2).

It is not a de Polignac number, because 77893921 - 2¹ = 77893919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77893931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42796 + ... + 44578.

It is an arithmetic number, because the mean of its divisors is an integer number (7517776).

Almost surely, 2^77893921 is an apocalyptic number.

77893921 is the 12481-st triangular number and also the 6241-st hexagonal number.

77893921 is the 4161-st centered nonagonal number.

It is an amenable number.

77893921 is a deficient number, since it is larger than the sum of its proper divisors (12319391).

77893921 is an equidigital number, since it uses as much as digits as its factorization.

77893921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1948 (or 1869 counting only the distinct ones).

The product of its digits is 190512, while the sum is 46.

The square root of 77893921 is about 8825.7532822983. The cubic root of 77893921 is about 427.0720882628.

The spelling of 77893921 in words is "seventy-seven million, eight hundred ninety-three thousand, nine hundred twenty-one".