51440551 has 2 divisors, whose sum is σ = 51440552. Its totient is φ = 51440550.

The previous prime is 51440539. The next prime is 51440561. The reversal of 51440551 is 15504415.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51440551 is a prime.

It is a super-2 number, since 2×51440551² = 5292260574367202, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51440531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25720275 + 25720276.

It is an arithmetic number, because the mean of its divisors is an integer number (25720276).

Almost surely, 2^51440551 is an apocalyptic number.

51440551 is a deficient number, since it is larger than the sum of its proper divisors (1).

51440551 is an equidigital number, since it uses as much as digits as its factorization.

51440551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 51440551 is about 7172.2068430853. The cubic root of 51440551 is about 371.9077289745.

Adding to 51440551 its reverse (15504415), we get a palindrome (66944966).

The spelling of 51440551 in words is "fifty-one million, four hundred forty thousand, five hundred fifty-one".