72391549 has 2 divisors, whose sum is σ = 72391550. Its totient is φ = 72391548.

The previous prime is 72391547. The next prime is 72391589. The reversal of 72391549 is 94519327.

It is an a-pointer prime, because the next prime (72391589) can be obtained adding 72391549 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72369049 + 22500 = 8507^2 + 150^2 .

It is a cyclic number.

It is not a de Polignac number, because 72391549 - 2¹ = 72391547 is a prime.

Together with 72391547, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72391547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36195774 + 36195775.

It is an arithmetic number, because the mean of its divisors is an integer number (36195775).

Almost surely, 2^72391549 is an apocalyptic number.

It is an amenable number.

72391549 is a deficient number, since it is larger than the sum of its proper divisors (1).

72391549 is an equidigital number, since it uses as much as digits as its factorization.

72391549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 40.

The square root of 72391549 is about 8508.3223375704. The cubic root of 72391549 is about 416.7695264634.

The spelling of 72391549 in words is "seventy-two million, three hundred ninety-one thousand, five hundred forty-nine".