51378746 has 4 divisors (see below), whose sum is σ = 77068122. Its totient is φ = 25689372.

The previous prime is 51378737. The next prime is 51378763. The reversal of 51378746 is 64787315.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 64787315 = 5 ⋅12957463.

It can be written as a sum of positive squares in only one way, i.e., 26925721 + 24453025 = 5189^2 + 4945^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12844685 + ... + 12844688.

Almost surely, 2^51378746 is an apocalyptic number.

51378746 is a deficient number, since it is larger than the sum of its proper divisors (25689376).

51378746 is a wasteful number, since it uses less digits than its factorization.

51378746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25689375.

The product of its digits is 141120, while the sum is 41.

The square root of 51378746 is about 7167.8969021604. The cubic root of 51378746 is about 371.7587222177.

The spelling of 51378746 in words is "fifty-one million, three hundred seventy-eight thousand, seven hundred forty-six".