51281245 has 4 divisors (see below), whose sum is σ = 61537500. Its totient is φ = 41024992.

The previous prime is 51281239. The next prime is 51281257. The reversal of 51281245 is 54218215.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6095961 + 45185284 = 2469^2 + 6722^2 .

It is a cyclic number.

It is not a de Polignac number, because 51281245 - 2⁵ = 51281213 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5128120 + ... + 5128129.

It is an arithmetic number, because the mean of its divisors is an integer number (15384375).

Almost surely, 2^51281245 is an apocalyptic number.

It is an amenable number.

51281245 is a deficient number, since it is larger than the sum of its proper divisors (10256255).

51281245 is a wasteful number, since it uses less digits than its factorization.

51281245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10256254.

The product of its digits is 3200, while the sum is 28.

The square root of 51281245 is about 7161.0924445925. The cubic root of 51281245 is about 371.5234122070.

The spelling of 51281245 in words is "fifty-one million, two hundred eighty-one thousand, two hundred forty-five".