51178491 has 72 divisors (see below), whose sum is σ = 94610880. Its totient is φ = 26417664.

The previous prime is 51178459. The next prime is 51178493. The reversal of 51178491 is 19487115.

It is not a de Polignac number, because 51178491 - 2⁵ = 51178459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51178493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 452851 + ... + 452963.

It is an arithmetic number, because the mean of its divisors is an integer number (1314040).

Almost surely, 2^51178491 is an apocalyptic number.

51178491 is a deficient number, since it is larger than the sum of its proper divisors (43432389).

51178491 is a wasteful number, since it uses less digits than its factorization.

51178491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225 (or 215 counting only the distinct ones).

The product of its digits is 10080, while the sum is 36.

The square root of 51178491 is about 7153.9143830493. The cubic root of 51178491 is about 371.2751015235.

The spelling of 51178491 in words is "fifty-one million, one hundred seventy-eight thousand, four hundred ninety-one".