77420137 has 2 divisors, whose sum is σ = 77420138. Its totient is φ = 77420136.

The previous prime is 77420071. The next prime is 77420143. The reversal of 77420137 is 73102477.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68293696 + 9126441 = 8264^2 + 3021^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77420137 is a prime.

It is a super-2 number, since 2×77420137² = 11987755226197538, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 77420099 and 77420108.

It is not a weakly prime, because it can be changed into another prime (77421137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38710068 + 38710069.

It is an arithmetic number, because the mean of its divisors is an integer number (38710069).

Almost surely, 2^77420137 is an apocalyptic number.

It is an amenable number.

77420137 is a deficient number, since it is larger than the sum of its proper divisors (1).

77420137 is an equidigital number, since it uses as much as digits as its factorization.

77420137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8232, while the sum is 31.

The square root of 77420137 is about 8798.8713480764. The cubic root of 77420137 is about 426.2044486544.

The spelling of 77420137 in words is "seventy-seven million, four hundred twenty thousand, one hundred thirty-seven".