51249766 has 4 divisors (see below), whose sum is σ = 76874652. Its totient is φ = 25624882.

The previous prime is 51249743. The next prime is 51249767. The reversal of 51249766 is 66794215.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51249767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12812440 + ... + 12812443.

It is an arithmetic number, because the mean of its divisors is an integer number (19218663).

Almost surely, 2^51249766 is an apocalyptic number.

51249766 is a deficient number, since it is larger than the sum of its proper divisors (25624886).

51249766 is a wasteful number, since it uses less digits than its factorization.

51249766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25624885.

The product of its digits is 90720, while the sum is 40.

The square root of 51249766 is about 7158.8941883506. The cubic root of 51249766 is about 371.4473767458.

The spelling of 51249766 in words is "fifty-one million, two hundred forty-nine thousand, seven hundred sixty-six".