72180457 has 4 divisors (see below), whose sum is σ = 72264960. Its totient is φ = 72095956.

The previous prime is 72180439. The next prime is 72180469. The reversal of 72180457 is 75408127.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75408127 = 1277 ⋅59051.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72180457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72180557) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 40957 + ... + 42682.

It is an arithmetic number, because the mean of its divisors is an integer number (18066240).

Almost surely, 2^72180457 is an apocalyptic number.

It is an amenable number.

72180457 is a deficient number, since it is larger than the sum of its proper divisors (84503).

72180457 is an equidigital number, since it uses as much as digits as its factorization.

72180457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84502.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 72180457 is about 8495.9082504462. The cubic root of 72180457 is about 416.3640354654.

The spelling of 72180457 in words is "seventy-two million, one hundred eighty thousand, four hundred fifty-seven".