51681494 has 8 divisors (see below), whose sum is σ = 77912400. Its totient is φ = 25710696.

The previous prime is 51681493. The next prime is 51681517. The reversal of 51681494 is 49418615.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51681491) 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, 64529 + ... + 65324.

It is an arithmetic number, because the mean of its divisors is an integer number (9739050).

Almost surely, 2^51681494 is an apocalyptic number.

51681494 is a deficient number, since it is larger than the sum of its proper divisors (26230906).

51681494 is a wasteful number, since it uses less digits than its factorization.

51681494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130054.

The product of its digits is 34560, while the sum is 38.

The square root of 51681494 is about 7188.9842119732. The cubic root of 51681494 is about 372.4874857289.

The spelling of 51681494 in words is "fifty-one million, six hundred eighty-one thousand, four hundred ninety-four".