72506999 has 4 divisors (see below), whose sum is σ = 72524640. Its totient is φ = 72489360.

The previous prime is 72506981. The next prime is 72507011. The reversal of 72506999 is 99960527.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99960527 = 17 ⋅5880031.

It is a cyclic number.

It is not a de Polignac number, because 72506999 - 2⁸ = 72506743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72506969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 962 + ... + 12080.

It is an arithmetic number, because the mean of its divisors is an integer number (18131160).

Almost surely, 2^72506999 is an apocalyptic number.

72506999 is a deficient number, since it is larger than the sum of its proper divisors (17641).

72506999 is a wasteful number, since it uses less digits than its factorization.

72506999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17640.

The product of its (nonzero) digits is 306180, while the sum is 47.

The square root of 72506999 is about 8515.1041684762. The cubic root of 72506999 is about 416.9909633882.

The spelling of 72506999 in words is "seventy-two million, five hundred six thousand, nine hundred ninety-nine".