51989993 has 8 divisors (see below), whose sum is σ = 57132000. Its totient is φ = 46917280.

The previous prime is 51989957. The next prime is 51990041. The reversal of 51989993 is 39998915.

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 51989993 - 2⁸ = 51989737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51989933) 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, 15743 + ... + 18756.

It is an arithmetic number, because the mean of its divisors is an integer number (7141500).

Almost surely, 2^51989993 is an apocalyptic number.

It is an amenable number.

51989993 is a deficient number, since it is larger than the sum of its proper divisors (5142007).

51989993 is a wasteful number, since it uses less digits than its factorization.

51989993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34647.

The product of its digits is 787320, while the sum is 53.

The square root of 51989993 is about 7210.4086569348. The cubic root of 51989993 is about 373.2271710437.

The spelling of 51989993 in words is "fifty-one million, nine hundred eighty-nine thousand, nine hundred ninety-three".