77072081 has 2 divisors, whose sum is σ = 77072082. Its totient is φ = 77072080.

The previous prime is 77072059. The next prime is 77072137. The reversal of 77072081 is 18027077.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74995600 + 2076481 = 8660^2 + 1441^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77072081 is a prime.

It is a super-2 number, since 2×77072081² = 11880211339341122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77072381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38536040 + 38536041.

It is an arithmetic number, because the mean of its divisors is an integer number (38536041).

Almost surely, 2^77072081 is an apocalyptic number.

It is an amenable number.

77072081 is a deficient number, since it is larger than the sum of its proper divisors (1).

77072081 is an equidigital number, since it uses as much as digits as its factorization.

77072081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5488, while the sum is 32.

The square root of 77072081 is about 8779.0706227937. The cubic root of 77072081 is about 425.5647964957.

The spelling of 77072081 in words is "seventy-seven million, seventy-two thousand, eighty-one".