51005015655 has 48 divisors (see below), whose sum is σ = 90589840992. Its totient is φ = 24484768000.

The previous prime is 51005015639. The next prime is 51005015657. The reversal of 51005015655 is 55651050015.

It is not a de Polignac number, because 51005015655 - 2⁴ = 51005015639 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51005015657) 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 47 ways as a sum of consecutive naturals, for example, 44197 + ... + 322433.

It is an arithmetic number, because the mean of its divisors is an integer number (1887288354).

Almost surely, 2^51005015655 is an apocalyptic number.

51005015655 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51005015655 is a deficient number, since it is larger than the sum of its proper divisors (39584825337).

51005015655 is a wasteful number, since it uses less digits than its factorization.

51005015655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278368 (or 278357 counting only the distinct ones).

The product of its (nonzero) digits is 18750, while the sum is 33.

The spelling of 51005015655 in words is "fifty-one billion, five million, fifteen thousand, six hundred fifty-five".