39391690 has 16 divisors (see below), whose sum is σ = 76359528. Its totient is φ = 14544576.

The previous prime is 39391633. The next prime is 39391697. The reversal of 39391690 is 9619393.

It can be written as a sum of positive squares in 4 ways, for example, as 19704721 + 19686969 = 4439^2 + 4437^2 .

It is a super-2 number, since 2×39391690² = 3103410482112200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (39391697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151377 + ... + 151636.

Almost surely, 2^39391690 is an apocalyptic number.

39391690 is a deficient number, since it is larger than the sum of its proper divisors (36967838).

39391690 is a wasteful number, since it uses less digits than its factorization.

39391690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303033.

The product of its (nonzero) digits is 39366, while the sum is 40.

The square root of 39391690 is about 6276.2799491418. The cubic root of 39391690 is about 340.2526668585.

The spelling of 39391690 in words is "thirty-nine million, three hundred ninety-one thousand, six hundred ninety".