72731387 has 2 divisors, whose sum is σ = 72731388. Its totient is φ = 72731386.

The previous prime is 72731371. The next prime is 72731441. The reversal of 72731387 is 78313727.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 72731387 - 2⁴ = 72731371 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72731387.

It is not a weakly prime, because it can be changed into another prime (72731327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36365693 + 36365694.

It is an arithmetic number, because the mean of its divisors is an integer number (36365694).

Almost surely, 2^72731387 is an apocalyptic number.

72731387 is a deficient number, since it is larger than the sum of its proper divisors (1).

72731387 is an equidigital number, since it uses as much as digits as its factorization.

72731387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 49392, while the sum is 38.

The square root of 72731387 is about 8528.2698714335. The cubic root of 72731387 is about 417.4206755243.

The spelling of 72731387 in words is "seventy-two million, seven hundred thirty-one thousand, three hundred eighty-seven".