51981589 has 8 divisors (see below), whose sum is σ = 57048768. Its totient is φ = 46971360.

The previous prime is 51981583. The next prime is 51981613. The reversal of 51981589 is 98518915.

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

It is a cyclic number.

It is not a de Polignac number, because 51981589 - 2³ = 51981581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51981581) 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, 12312 + ... + 15985.

It is an arithmetic number, because the mean of its divisors is an integer number (7131096).

Almost surely, 2^51981589 is an apocalyptic number.

It is an amenable number.

51981589 is a deficient number, since it is larger than the sum of its proper divisors (5067179).

51981589 is a wasteful number, since it uses less digits than its factorization.

51981589 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28475.

The product of its digits is 129600, while the sum is 46.

The square root of 51981589 is about 7209.8258647487. The cubic root of 51981589 is about 373.2070596723.

The spelling of 51981589 in words is "fifty-one million, nine hundred eighty-one thousand, five hundred eighty-nine".