7872639 has 8 divisors (see below), whose sum is σ = 10550400. Its totient is φ = 5221656.

The previous prime is 7872637. The next prime is 7872643. The reversal of 7872639 is 9362787.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 7872639 - 2¹ = 7872637 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

7872639 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 7872639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7872637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5997 + ... + 7190.

It is an arithmetic number, because the mean of its divisors is an integer number (1318800).

Almost surely, 2^7872639 is an apocalyptic number.

7872639 is a deficient number, since it is larger than the sum of its proper divisors (2677761).

7872639 is a wasteful number, since it uses less digits than its factorization.

7872639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13389.

The product of its digits is 127008, while the sum is 42.

The square root of 7872639 is about 2805.8223393508. The cubic root of 7872639 is about 198.9329757534.

The spelling of 7872639 in words is "seven million, eight hundred seventy-two thousand, six hundred thirty-nine".