55915861 has 2 divisors, whose sum is σ = 55915862. Its totient is φ = 55915860.

The previous prime is 55915831. The next prime is 55915897. The reversal of 55915861 is 16851955.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51480625 + 4435236 = 7175^2 + 2106^2 .

It is a cyclic number.

It is not a de Polignac number, because 55915861 - 2¹³ = 55907669 is a prime.

It is a super-2 number, since 2×55915861² = 6253167022742642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55915831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27957930 + 27957931.

It is an arithmetic number, because the mean of its divisors is an integer number (27957931).

Almost surely, 2^55915861 is an apocalyptic number.

It is an amenable number.

55915861 is a deficient number, since it is larger than the sum of its proper divisors (1).

55915861 is an equidigital number, since it uses as much as digits as its factorization.

55915861 is an evil number, because the sum of its binary digits is even.

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

The square root of 55915861 is about 7477.6908868982. The cubic root of 55915861 is about 382.3945308481.

The spelling of 55915861 in words is "fifty-five million, nine hundred fifteen thousand, eight hundred sixty-one".