27972989 has 4 divisors (see below), whose sum is σ = 30516000. Its totient is φ = 25429980.

The previous prime is 27972979. The next prime is 27973013. The reversal of 27972989 is 98927972.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27972989 is a prime.

It is a super-2 number, since 2×27972989² = 1564976227188242, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27972989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27972949) 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, 1271489 + ... + 1271510.

It is an arithmetic number, because the mean of its divisors is an integer number (7629000).

Almost surely, 2^27972989 is an apocalyptic number.

It is an amenable number.

27972989 is a deficient number, since it is larger than the sum of its proper divisors (2543011).

27972989 is a wasteful number, since it uses less digits than its factorization.

27972989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2543010.

The product of its digits is 1143072, while the sum is 53.

The square root of 27972989 is about 5288.9497066998. The cubic root of 27972989 is about 303.5612213619.

The spelling of 27972989 in words is "twenty-seven million, nine hundred seventy-two thousand, nine hundred eighty-nine".