51213769 has 8 divisors (see below), whose sum is σ = 52045448. Its totient is φ = 50388480.

The previous prime is 51213761. The next prime is 51213781. The reversal of 51213769 is 96731215.

It can be written as a sum of positive squares in 4 ways, for example, as 7812025 + 43401744 = 2795^2 + 6588^2 .

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 51213769 - 2³ = 51213761 is a prime.

It is a super-2 number, since 2×51213769² = 5245700270370722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51213761) 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, 16099 + ... + 19015.

It is an arithmetic number, because the mean of its divisors is an integer number (6505681).

Almost surely, 2^51213769 is an apocalyptic number.

It is an amenable number.

51213769 is a deficient number, since it is larger than the sum of its proper divisors (831679).

51213769 is a wasteful number, since it uses less digits than its factorization.

51213769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3195.

The product of its digits is 11340, while the sum is 34.

The square root of 51213769 is about 7156.3796014465. The cubic root of 51213769 is about 371.3603901830.

The spelling of 51213769 in words is "fifty-one million, two hundred thirteen thousand, seven hundred sixty-nine".