51404642 has 4 divisors (see below), whose sum is σ = 77106966. Its totient is φ = 25702320.

The previous prime is 51404623. The next prime is 51404677. The reversal of 51404642 is 24640415.

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., 50537881 + 866761 = 7109^2 + 931^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12851159 + ... + 12851162.

Almost surely, 2^51404642 is an apocalyptic number.

51404642 is a deficient number, since it is larger than the sum of its proper divisors (25702324).

51404642 is a wasteful number, since it uses less digits than its factorization.

51404642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25702323.

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 51404642 is about 7169.7030621916. The cubic root of 51404642 is about 371.8211698746.

The spelling of 51404642 in words is "fifty-one million, four hundred four thousand, six hundred forty-two".