51781897 has 8 divisors (see below), whose sum is σ = 54857600. Its totient is φ = 48741264.

The previous prime is 51781871. The next prime is 51781909. The reversal of 51781897 is 79818715.

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 51781897 - 2²³ = 43393289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51781817) 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, 5697 + ... + 11662.

It is an arithmetic number, because the mean of its divisors is an integer number (6857200).

Almost surely, 2^51781897 is an apocalyptic number.

It is an amenable number.

51781897 is a deficient number, since it is larger than the sum of its proper divisors (3075703).

51781897 is a wasteful number, since it uses less digits than its factorization.

51781897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17535.

The product of its digits is 141120, while the sum is 46.

The square root of 51781897 is about 7195.9639382087. The cubic root of 51781897 is about 372.7285434438.

The spelling of 51781897 in words is "fifty-one million, seven hundred eighty-one thousand, eight hundred ninety-seven".