51119981 has 4 divisors (see below), whose sum is σ = 55767264. Its totient is φ = 46472700.

The previous prime is 51119951. The next prime is 51119987. The reversal of 51119981 is 18991115.

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 not a de Polignac number, because 51119981 - 2¹⁸ = 50857837 is a prime.

It is a super-2 number, since 2×51119981² = 5226504914880722, 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 (51119987) 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, 2323625 + ... + 2323646.

It is an arithmetic number, because the mean of its divisors is an integer number (13941816).

Almost surely, 2^51119981 is an apocalyptic number.

It is an amenable number.

51119981 is a deficient number, since it is larger than the sum of its proper divisors (4647283).

51119981 is a wasteful number, since it uses less digits than its factorization.

51119981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4647282.

The product of its digits is 3240, while the sum is 35.

The square root of 51119981 is about 7149.8238439839. The cubic root of 51119981 is about 371.1335603575.

The spelling of 51119981 in words is "fifty-one million, one hundred nineteen thousand, nine hundred eighty-one".