72542405 has 18 divisors (see below), whose sum is σ = 94585014. Its totient is φ = 53386944.

The previous prime is 72542381. The next prime is 72542411. The reversal of 72542405 is 50424527.

It is a happy number.

It can be written as a sum of positive squares in 9 ways, for example, as 6461764 + 66080641 = 2542^2 + 8129^2 .

It is not a de Polignac number, because 72542405 - 2¹⁶ = 72476869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 247439 + ... + 247731.

It is an arithmetic number, because the mean of its divisors is an integer number (5254723).

Almost surely, 2^72542405 is an apocalyptic number.

It is an amenable number.

72542405 is a deficient number, since it is larger than the sum of its proper divisors (22042609).

72542405 is an equidigital number, since it uses as much as digits as its factorization.

72542405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 29.

The square root of 72542405 is about 8517.1829262967. The cubic root of 72542405 is about 417.0588261682.

The spelling of 72542405 in words is "seventy-two million, five hundred forty-two thousand, four hundred five".