51901778 has 4 divisors (see below), whose sum is σ = 77852670. Its totient is φ = 25950888.

The previous prime is 51901757. The next prime is 51901783. The reversal of 51901778 is 87710915.

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., 42211009 + 9690769 = 6497^2 + 3113^2 .

It is a super-2 number, since 2×51901778² = 5387589119122568, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12975443 + ... + 12975446.

Almost surely, 2^51901778 is an apocalyptic number.

51901778 is a deficient number, since it is larger than the sum of its proper divisors (25950892).

51901778 is a wasteful number, since it uses less digits than its factorization.

51901778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25950891.

The product of its (nonzero) digits is 17640, while the sum is 38.

The square root of 51901778 is about 7204.2888615047. The cubic root of 51901778 is about 373.0159581277.

The spelling of 51901778 in words is "fifty-one million, nine hundred one thousand, seven hundred seventy-eight".