53185981 has 2 divisors, whose sum is σ = 53185982. Its totient is φ = 53185980.

The previous prime is 53185933. The next prime is 53186011. The reversal of 53185981 is 18958135.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34987225 + 18198756 = 5915^2 + 4266^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-53185981 is a prime.

It is a super-2 number, since 2×53185981² = 5657497149864722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53185931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26592990 + 26592991.

It is an arithmetic number, because the mean of its divisors is an integer number (26592991).

Almost surely, 2^53185981 is an apocalyptic number.

It is an amenable number.

53185981 is a deficient number, since it is larger than the sum of its proper divisors (1).

53185981 is an equidigital number, since it uses as much as digits as its factorization.

53185981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43200, while the sum is 40.

The square root of 53185981 is about 7292.8719308651. The cubic root of 53185981 is about 376.0674321680.

The spelling of 53185981 in words is "fifty-three million, one hundred eighty-five thousand, nine hundred eighty-one".