51078555 has 48 divisors (see below), whose sum is σ = 101687040. Its totient is φ = 23457600.

The previous prime is 51078553. The next prime is 51078569. The reversal of 51078555 is 55587015.

It is not a de Polignac number, because 51078555 - 2¹ = 51078553 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (51078553) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6690 + ... + 12120.

It is an arithmetic number, because the mean of its divisors is an integer number (2118480).

Almost surely, 2^51078555 is an apocalyptic number.

51078555 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51078555 is a deficient number, since it is larger than the sum of its proper divisors (50608485).

51078555 is a wasteful number, since it uses less digits than its factorization.

51078555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5472 (or 5469 counting only the distinct ones).

The product of its (nonzero) digits is 35000, while the sum is 36.

The square root of 51078555 is about 7146.9262623872. The cubic root of 51078555 is about 371.0332816703.

The spelling of 51078555 in words is "fifty-one million, seventy-eight thousand, five hundred fifty-five".