51855553 has 2 divisors, whose sum is σ = 51855554. Its totient is φ = 51855552.

The previous prime is 51855533. The next prime is 51855563. The reversal of 51855553 is 35555815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44715969 + 7139584 = 6687^2 + 2672^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51855553 is a prime.

It is not a weakly prime, because it can be changed into another prime (51855533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25927776 + 25927777.

It is an arithmetic number, because the mean of its divisors is an integer number (25927777).

Almost surely, 2^51855553 is an apocalyptic number.

It is an amenable number.

51855553 is a deficient number, since it is larger than the sum of its proper divisors (1).

51855553 is an equidigital number, since it uses as much as digits as its factorization.

51855553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75000, while the sum is 37.

The square root of 51855553 is about 7201.0799884462. The cubic root of 51855553 is about 372.9051861736.

The spelling of 51855553 in words is "fifty-one million, eight hundred fifty-five thousand, five hundred fifty-three".