51005553 has 4 divisors (see below), whose sum is σ = 68007408. Its totient is φ = 34003700.

The previous prime is 51005551. The next prime is 51005561. The reversal of 51005553 is 35550015.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51005553 - 2¹ = 51005551 is a prime.

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 3 ways as a sum of consecutive naturals, for example, 8500923 + ... + 8500928.

It is an arithmetic number, because the mean of its divisors is an integer number (17001852).

Almost surely, 2^51005553 is an apocalyptic number.

It is an amenable number.

51005553 is a deficient number, since it is larger than the sum of its proper divisors (17001855).

51005553 is a wasteful number, since it uses less digits than its factorization.

51005553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17001854.

The product of its (nonzero) digits is 1875, while the sum is 24.

The square root of 51005553 is about 7141.8172057257. The cubic root of 51005553 is about 370.8564358568.

Adding to 51005553 its reverse (35550015), we get a palindrome (86555568).

The spelling of 51005553 in words is "fifty-one million, five thousand, five hundred fifty-three".