53947991 has 2 divisors, whose sum is σ = 53947992. Its totient is φ = 53947990.

The previous prime is 53947981. The next prime is 53948047. The reversal of 53947991 is 19974935.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 53947991 - 2²² = 49753687 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 (53947981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26973995 + 26973996.

It is an arithmetic number, because the mean of its divisors is an integer number (26973996).

Almost surely, 2^53947991 is an apocalyptic number.

53947991 is a deficient number, since it is larger than the sum of its proper divisors (1).

53947991 is an equidigital number, since it uses as much as digits as its factorization.

53947991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 306180, while the sum is 47.

The square root of 53947991 is about 7344.9296116437. The cubic root of 53947991 is about 377.8549292606.

The spelling of 53947991 in words is "fifty-three million, nine hundred forty-seven thousand, nine hundred ninety-one".