51951866 has 4 divisors (see below), whose sum is σ = 77927802. Its totient is φ = 25975932.

The previous prime is 51951859. The next prime is 51951883. The reversal of 51951866 is 66815915.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66815915 = 5 ⋅13363183.

It can be written as a sum of positive squares in only one way, i.e., 50708641 + 1243225 = 7121^2 + 1115^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12987965 + ... + 12987968.

Almost surely, 2^51951866 is an apocalyptic number.

51951866 is a deficient number, since it is larger than the sum of its proper divisors (25975936).

51951866 is a wasteful number, since it uses less digits than its factorization.

51951866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25975935.

The product of its digits is 64800, while the sum is 41.

The square root of 51951866 is about 7207.7642858240. The cubic root of 51951866 is about 373.1359130182.

The spelling of 51951866 in words is "fifty-one million, nine hundred fifty-one thousand, eight hundred sixty-six".