39289981 has 2 divisors, whose sum is σ = 39289982. Its totient is φ = 39289980.

The previous prime is 39289973. The next prime is 39289993. The reversal of 39289981 is 18998293.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39262756 + 27225 = 6266^2 + 165^2 .

It is a cyclic number.

It is not a de Polignac number, because 39289981 - 2³ = 39289973 is a prime.

It is a super-2 number, since 2×39289981² = 3087405213960722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39289961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19644990 + 19644991.

It is an arithmetic number, because the mean of its divisors is an integer number (19644991).

Almost surely, 2^39289981 is an apocalyptic number.

It is an amenable number.

39289981 is a deficient number, since it is larger than the sum of its proper divisors (1).

39289981 is an equidigital number, since it uses as much as digits as its factorization.

39289981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 49.

The square root of 39289981 is about 6268.1720620927. The cubic root of 39289981 is about 339.9595713175.

The spelling of 39289981 in words is "thirty-nine million, two hundred eighty-nine thousand, nine hundred eighty-one".