7977938 has 4 divisors (see below), whose sum is σ = 11966910. Its totient is φ = 3988968.

The previous prime is 7977923. The next prime is 7977961. The reversal of 7977938 is 8397797.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8397797 = 53 ⋅158449.

It can be written as a sum of positive squares in only one way, i.e., 6568969 + 1408969 = 2563^2 + 1187^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1994483 + ... + 1994486.

Almost surely, 2^7977938 is an apocalyptic number.

7977938 is a deficient number, since it is larger than the sum of its proper divisors (3988972).

7977938 is a wasteful number, since it uses less digits than its factorization.

7977938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3988971.

The product of its digits is 666792, while the sum is 50.

The square root of 7977938 is about 2824.5243847416. The cubic root of 7977938 is about 199.8159807365.

The spelling of 7977938 in words is "seven million, nine hundred seventy-seven thousand, nine hundred thirty-eight".