51989121 has 12 divisors (see below), whose sum is σ = 77877072. Its totient is φ = 34659252.

The previous prime is 51989117. The next prime is 51989123. The reversal of 51989121 is 12198915.

It is not a de Polignac number, because 51989121 - 2² = 51989117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51989123) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 106731 + ... + 107216.

It is an arithmetic number, because the mean of its divisors is an integer number (6489756).

Almost surely, 2^51989121 is an apocalyptic number.

It is an amenable number.

51989121 is a deficient number, since it is larger than the sum of its proper divisors (25887951).

51989121 is an equidigital number, since it uses as much as digits as its factorization.

51989121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213962 (or 213950 counting only the distinct ones).

The product of its digits is 6480, while the sum is 36.

The square root of 51989121 is about 7210.3481885412. The cubic root of 51989121 is about 373.2250843862.

The spelling of 51989121 in words is "fifty-one million, nine hundred eighty-nine thousand, one hundred twenty-one".