51451787 has 4 divisors (see below), whose sum is σ = 52156680. Its totient is φ = 50746896.

The previous prime is 51451781. The next prime is 51451811. The reversal of 51451787 is 78715415.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78715415 = 5 ⋅15743083.

It is a cyclic number.

It is not a de Polignac number, because 51451787 - 2¹⁴ = 51435403 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51451787.

It is not an unprimeable number, because it can be changed into a prime (51451781) 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, 352337 + ... + 352482.

It is an arithmetic number, because the mean of its divisors is an integer number (13039170).

Almost surely, 2^51451787 is an apocalyptic number.

51451787 is a deficient number, since it is larger than the sum of its proper divisors (704893).

51451787 is an equidigital number, since it uses as much as digits as its factorization.

51451787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704892.

The product of its digits is 39200, while the sum is 38.

The square root of 51451787 is about 7172.9901017637. The cubic root of 51451787 is about 371.9348052204.

The spelling of 51451787 in words is "fifty-one million, four hundred fifty-one thousand, seven hundred eighty-seven".