7977913 has 8 divisors (see below), whose sum is σ = 8524008. Its totient is φ = 7440384.

The previous prime is 7977899. The next prime is 7977923. The reversal of 7977913 is 3197797.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 121104 + 7856809 = 348^2 + 2803^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7977913 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7977913.

It is not an unprimeable number, because it can be changed into a prime (7977923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156 + ... + 3997.

It is an arithmetic number, because the mean of its divisors is an integer number (1065501).

Almost surely, 2^7977913 is an apocalyptic number.

It is an amenable number.

7977913 is a deficient number, since it is larger than the sum of its proper divisors (546095).

7977913 is a wasteful number, since it uses less digits than its factorization.

7977913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4283.

The product of its digits is 83349, while the sum is 43.

The square root of 7977913 is about 2824.5199592143. The cubic root of 7977913 is about 199.8157720190.

The spelling of 7977913 in words is "seven million, nine hundred seventy-seven thousand, nine hundred thirteen".