72973777 has 2 divisors, whose sum is σ = 72973778. Its totient is φ = 72973776.

The previous prime is 72973763. The next prime is 72973781. The reversal of 72973777 is 77737927.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62110161 + 10863616 = 7881^2 + 3296^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72973777 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72973777.

It is not a weakly prime, because it can be changed into another prime (72973477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36486888 + 36486889.

It is an arithmetic number, because the mean of its divisors is an integer number (36486889).

Almost surely, 2^72973777 is an apocalyptic number.

It is an amenable number.

72973777 is a deficient number, since it is larger than the sum of its proper divisors (1).

72973777 is an equidigital number, since it uses as much as digits as its factorization.

72973777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 907578, while the sum is 49.

The square root of 72973777 is about 8542.4690224782. The cubic root of 72973777 is about 417.8838703517.

The spelling of 72973777 in words is "seventy-two million, nine hundred seventy-three thousand, seven hundred seventy-seven".