55871989 has 4 divisors (see below), whose sum is σ = 58812640. Its totient is φ = 52931340.

The previous prime is 55871987. The next prime is 55872077. The reversal of 55871989 is 98917855.

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 not a de Polignac number, because 55871989 - 2¹ = 55871987 is a prime.

It is a super-2 number, since 2×55871989² = 6243358309632242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55871987) 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, 1470297 + ... + 1470334.

It is an arithmetic number, because the mean of its divisors is an integer number (14703160).

Almost surely, 2^55871989 is an apocalyptic number.

It is an amenable number.

55871989 is a deficient number, since it is larger than the sum of its proper divisors (2940651).

55871989 is a wasteful number, since it uses less digits than its factorization.

55871989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2940650.

The product of its digits is 907200, while the sum is 52.

The square root of 55871989 is about 7474.7567853409. The cubic root of 55871989 is about 382.2944948171.

The spelling of 55871989 in words is "fifty-five million, eight hundred seventy-one thousand, nine hundred eighty-nine".