51491242 has 32 divisors (see below), whose sum is σ = 86433984. Its totient is φ = 22809600.

The previous prime is 51491213. The next prime is 51491263. The reversal of 51491242 is 24219415.

It is a self number, because there is not a number n which added to its sum of digits gives 51491242.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266698 + ... + 266890.

It is an arithmetic number, because the mean of its divisors is an integer number (2701062).

Almost surely, 2^51491242 is an apocalyptic number.

51491242 is a deficient number, since it is larger than the sum of its proper divisors (34942742).

51491242 is a wasteful number, since it uses less digits than its factorization.

51491242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454.

The product of its digits is 2880, while the sum is 28.

The square root of 51491242 is about 7175.7398224852. The cubic root of 51491242 is about 372.0298517302.

The spelling of 51491242 in words is "fifty-one million, four hundred ninety-one thousand, two hundred forty-two".