51005554 has 4 divisors (see below), whose sum is σ = 76508334. Its totient is φ = 25502776.

The previous prime is 51005551. The next prime is 51005561. The reversal of 51005554 is 45550015.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 33907329 + 17098225 = 5823^2 + 4135^2 .

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 as a sum of consecutive naturals, namely, 12751387 + ... + 12751390.

Almost surely, 2^51005554 is an apocalyptic number.

51005554 is a deficient number, since it is larger than the sum of its proper divisors (25502780).

51005554 is a wasteful number, since it uses less digits than its factorization.

51005554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25502779.

The product of its (nonzero) digits is 2500, while the sum is 25.

The square root of 51005554 is about 7141.8172757359. The cubic root of 51005554 is about 370.8564382804.

Adding to 51005554 its reverse (45550015), we get a palindrome (96555569).

The spelling of 51005554 in words is "fifty-one million, five thousand, five hundred fifty-four".