551865901 has 2 divisors, whose sum is σ = 551865902. Its totient is φ = 551865900.

The previous prime is 551865893. The next prime is 551865943. The reversal of 551865901 is 109568155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 551028676 + 837225 = 23474^2 + 915^2 .

It is a cyclic number.

It is not a de Polignac number, because 551865901 - 2³ = 551865893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (551865971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275932950 + 275932951.

It is an arithmetic number, because the mean of its divisors is an integer number (275932951).

Almost surely, 2^551865901 is an apocalyptic number.

It is an amenable number.

551865901 is a deficient number, since it is larger than the sum of its proper divisors (1).

551865901 is an equidigital number, since it uses as much as digits as its factorization.

551865901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54000, while the sum is 40.

The square root of 551865901 is about 23491.8262593609. The cubic root of 551865901 is about 820.2467535208.

It can be divided in two parts, 55 and 1865901, that added together give a square (1865956 = 1366²).

The spelling of 551865901 in words is "five hundred fifty-one million, eight hundred sixty-five thousand, nine hundred one".