7977697220 has 12 divisors (see below), whose sum is σ = 16753164204. Its totient is φ = 3191078880.

The previous prime is 7977697157. The next prime is 7977697237. The reversal of 7977697220 is 227967797.

It can be written as a sum of positive squares in 2 ways, for example, as 4488196036 + 3489501184 = 66994^2 + 59072^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199442411 + ... + 199442450.

It is an arithmetic number, because the mean of its divisors is an integer number (1396097017).

Almost surely, 2^7977697220 is an apocalyptic number.

It is an amenable number.

7977697220 is an abundant number, since it is smaller than the sum of its proper divisors (8775466984).

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

7977697220 is a wasteful number, since it uses less digits than its factorization.

7977697220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398884870 (or 398884868 counting only the distinct ones).

The product of its (nonzero) digits is 4667544, while the sum is 56.

The square root of 7977697220 is about 89317.9557535885. The cubic root of 7977697220 is about 1998.1397051881.

The spelling of 7977697220 in words is "seven billion, nine hundred seventy-seven million, six hundred ninety-seven thousand, two hundred twenty".