39997657 has 8 divisors (see below), whose sum is σ = 47186432. Its totient is φ = 33177600.

The previous prime is 39997631. The next prime is 39997687. The reversal of 39997657 is 75679993.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 39997657 - 2²³ = 31609049 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 39997598 and 39997607.

It is not an unprimeable number, because it can be changed into a prime (39997687) 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, 91944 + ... + 92377.

It is an arithmetic number, because the mean of its divisors is an integer number (5898304).

Almost surely, 2^39997657 is an apocalyptic number.

It is an amenable number.

39997657 is a deficient number, since it is larger than the sum of its proper divisors (7188775).

39997657 is a wasteful number, since it uses less digits than its factorization.

39997657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184359.

The product of its digits is 3214890, while the sum is 55.

The square root of 39997657 is about 6324.3700872103. The cubic root of 39997657 is about 341.9885117489.

The spelling of 39997657 in words is "thirty-nine million, nine hundred ninety-seven thousand, six hundred fifty-seven".