39129642 has 40 divisors (see below), whose sum is σ = 90713700. Its totient is φ = 12591936.

The previous prime is 39129641. The next prime is 39129653. The reversal of 39129642 is 24692193.

39129642 is a `hidden beast` number, since 3 + 9 + 1 + 2 + 9 + 642 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 37564641 + 1565001 = 6129^2 + 1251^2 .

It is a super-2 number, since 2×39129642² = 3062257766096328, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 39129597 and 39129606.

It is not an unprimeable number, because it can be changed into a prime (39129641) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 534 + ... + 8862.

Almost surely, 2^39129642 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 39129642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45356850).

39129642 is an abundant number, since it is smaller than the sum of its proper divisors (51584058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

39129642 is a wasteful number, since it uses less digits than its factorization.

39129642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8372 (or 8363 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 39129642 is about 6255.3690538609. The cubic root of 39129642 is about 339.4964923220.

The spelling of 39129642 in words is "thirty-nine million, one hundred twenty-nine thousand, six hundred forty-two".