72777737 has 2 divisors, whose sum is σ = 72777738. Its totient is φ = 72777736.

The previous prime is 72777721. The next prime is 72777781. The reversal of 72777737 is 73777727.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60590656 + 12187081 = 7784^2 + 3491^2 .

It is an emirp because it is prime and its reverse (73777727) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72777737 - 2⁴ = 72777721 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72777691 and 72777700.

It is not a weakly prime, because it can be changed into another prime (72777437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36388868 + 36388869.

It is an arithmetic number, because the mean of its divisors is an integer number (36388869).

Almost surely, 2^72777737 is an apocalyptic number.

It is an amenable number.

72777737 is a deficient number, since it is larger than the sum of its proper divisors (1).

72777737 is an equidigital number, since it uses as much as digits as its factorization.

72777737 is an evil number, because the sum of its binary digits is even.

The product of its digits is 705894, while the sum is 47.

The square root of 72777737 is about 8530.9868714000. The cubic root of 72777737 is about 417.5093274835.

The spelling of 72777737 in words is "seventy-two million, seven hundred seventy-seven thousand, seven hundred thirty-seven".