72987998 has 4 divisors (see below), whose sum is σ = 109482000. Its totient is φ = 36493998.

The previous prime is 72987997. The next prime is 72988001. The reversal of 72987998 is 89978927.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89978927 = 19 ⋅4735733.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72987997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18246998 + ... + 18247001.

It is an arithmetic number, because the mean of its divisors is an integer number (27370500).

Almost surely, 2^72987998 is an apocalyptic number.

72987998 is a deficient number, since it is larger than the sum of its proper divisors (36494002).

72987998 is a wasteful number, since it uses less digits than its factorization.

72987998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36494001.

The product of its digits is 4572288, while the sum is 59.

The square root of 72987998 is about 8543.3013525218. The cubic root of 72987998 is about 417.9110140773.

The spelling of 72987998 in words is "seventy-two million, nine hundred eighty-seven thousand, nine hundred ninety-eight".