72640787 has 4 divisors (see below), whose sum is σ = 73086600. Its totient is φ = 72194976.

The previous prime is 72640783. The next prime is 72640801. The reversal of 72640787 is 78704627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78704627 = 2243 ⋅35089.

It is a cyclic number.

It is not a de Polignac number, because 72640787 - 2² = 72640783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72640783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222662 + ... + 222987.

It is an arithmetic number, because the mean of its divisors is an integer number (18271650).

Almost surely, 2^72640787 is an apocalyptic number.

72640787 is a deficient number, since it is larger than the sum of its proper divisors (445813).

72640787 is a wasteful number, since it uses less digits than its factorization.

72640787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445812.

The product of its (nonzero) digits is 131712, while the sum is 41.

The square root of 72640787 is about 8522.9564706151. The cubic root of 72640787 is about 417.2472793753.

The spelling of 72640787 in words is "seventy-two million, six hundred forty thousand, seven hundred eighty-seven".