39494781 has 18 divisors (see below), whose sum is σ = 59167290. Its totient is φ = 25356576.

The previous prime is 39494761. The next prime is 39494783. The reversal of 39494781 is 18749493.

It can be written as a sum of positive squares in 3 ways, for example, as 632025 + 38862756 = 795^2 + 6234^2 .

It is not a de Polignac number, because 39494781 - 2⁶ = 39494717 is a prime.

It is a super-2 number, since 2×39494781² = 3119675452475922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39494783) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 101335 + ... + 101723.

Almost surely, 2^39494781 is an apocalyptic number.

It is an amenable number.

39494781 is a deficient number, since it is larger than the sum of its proper divisors (19672509).

39494781 is an equidigital number, since it uses as much as digits as its factorization.

39494781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 813 (or 421 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 39494781 is about 6284.4873299260. The cubic root of 39494781 is about 340.5492305279.

The spelling of 39494781 in words is "thirty-nine million, four hundred ninety-four thousand, seven hundred eighty-one".