51142978 has 4 divisors (see below), whose sum is σ = 76714470. Its totient is φ = 25571488.

The previous prime is 51142951. The next prime is 51142981. The reversal of 51142978 is 87924115.

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

It can be written as a sum of positive squares in only one way, i.e., 41049649 + 10093329 = 6407^2 + 3177^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12785743 + ... + 12785746.

Almost surely, 2^51142978 is an apocalyptic number.

51142978 is a deficient number, since it is larger than the sum of its proper divisors (25571492).

51142978 is a wasteful number, since it uses less digits than its factorization.

51142978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25571491.

The product of its digits is 20160, while the sum is 37.

The square root of 51142978 is about 7151.4318845949. The cubic root of 51142978 is about 371.1892051288.

The spelling of 51142978 in words is "fifty-one million, one hundred forty-two thousand, nine hundred seventy-eight".