51005559 has 64 divisors (see below), whose sum is σ = 84602880. Its totient is φ = 26949120.

The previous prime is 51005551. The next prime is 51005561. The reversal of 51005559 is 95550015.

It is not a de Polignac number, because 51005559 - 2³ = 51005551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51005551) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 761244 + ... + 761310.

It is an arithmetic number, because the mean of its divisors is an integer number (1321920).

Almost surely, 2^51005559 is an apocalyptic number.

51005559 is a gapful number since it is divisible by the number (59) formed by its first and last digit.

51005559 is a deficient number, since it is larger than the sum of its proper divisors (33597321).

51005559 is a wasteful number, since it uses less digits than its factorization.

51005559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180.

The product of its (nonzero) digits is 5625, while the sum is 30.

The square root of 51005559 is about 7141.8176257869. The cubic root of 51005559 is about 370.8564503986.

The spelling of 51005559 in words is "fifty-one million, five thousand, five hundred fifty-nine".