72780025 has 12 divisors (see below), whose sum is σ = 90486892. Its totient is φ = 58069440.

The previous prime is 72779969. The next prime is 72780047. The reversal of 72780025 is 52008727.

It can be written as a sum of positive squares in 6 ways, for example, as 11377129 + 61402896 = 3373^2 + 7836^2 .

It is not a de Polignac number, because 72780025 - 2⁹ = 72779513 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6259 + ... + 13591.

Almost surely, 2^72780025 is an apocalyptic number.

It is an amenable number.

72780025 is a deficient number, since it is larger than the sum of its proper divisors (17706867).

72780025 is a wasteful number, since it uses less digits than its factorization.

72780025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7740 (or 7735 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 72780025 is about 8531.1209697202. The cubic root of 72780025 is about 417.5137026829.

The spelling of 72780025 in words is "seventy-two million, seven hundred eighty thousand, twenty-five".