51505501 has 2 divisors, whose sum is σ = 51505502. Its totient is φ = 51505500.

The previous prime is 51505481. The next prime is 51505507. The reversal of 51505501 is 10550515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38007225 + 13498276 = 6165^2 + 3674^2 .

It is a cyclic number.

It is not a de Polignac number, because 51505501 - 2¹³ = 51497309 is a prime.

It is a super-2 number, since 2×51505501² = 5305633266522002, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51505507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25752750 + 25752751.

It is an arithmetic number, because the mean of its divisors is an integer number (25752751).

Almost surely, 2^51505501 is an apocalyptic number.

It is an amenable number.

51505501 is a deficient number, since it is larger than the sum of its proper divisors (1).

51505501 is an equidigital number, since it uses as much as digits as its factorization.

51505501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 625, while the sum is 22.

The square root of 51505501 is about 7176.7333098005. The cubic root of 51505501 is about 372.0641895053.

The spelling of 51505501 in words is "fifty-one million, five hundred five thousand, five hundred one".