53815991 has 2 divisors, whose sum is σ = 53815992. Its totient is φ = 53815990.

The previous prime is 53815981. The next prime is 53816003. The reversal of 53815991 is 19951835.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 53815991 - 2¹⁰ = 53814967 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53815901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26907995 + 26907996.

It is an arithmetic number, because the mean of its divisors is an integer number (26907996).

Almost surely, 2^53815991 is an apocalyptic number.

53815991 is a deficient number, since it is larger than the sum of its proper divisors (1).

53815991 is an equidigital number, since it uses as much as digits as its factorization.

53815991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48600, while the sum is 41.

The square root of 53815991 is about 7335.9383176251. The cubic root of 53815991 is about 377.5464989577.

The spelling of 53815991 in words is "fifty-three million, eight hundred fifteen thousand, nine hundred ninety-one".