51087769 has 4 divisors (see below), whose sum is σ = 51235344. Its totient is φ = 50940196.

The previous prime is 51087733. The next prime is 51087791. The reversal of 51087769 is 96778015.

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, and also an emirpimes, since its reverse is a distinct semiprime: 96778015 = 5 ⋅19355603.

It is a cyclic number.

It is not a de Polignac number, because 51087769 - 2²³ = 42699161 is a prime.

It is a super-2 number, since 2×51087769² = 5219920282794722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51087709) 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, 73267 + ... + 73960.

It is an arithmetic number, because the mean of its divisors is an integer number (12808836).

Almost surely, 2^51087769 is an apocalyptic number.

It is an amenable number.

51087769 is a deficient number, since it is larger than the sum of its proper divisors (147575).

51087769 is a wasteful number, since it uses less digits than its factorization.

51087769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147574.

The product of its (nonzero) digits is 105840, while the sum is 43.

The square root of 51087769 is about 7147.5708460987. The cubic root of 51087769 is about 371.0555904135.

The spelling of 51087769 in words is "fifty-one million, eighty-seven thousand, seven hundred sixty-nine".