39891242 has 4 divisors (see below), whose sum is σ = 59836866. Its totient is φ = 19945620.

The previous prime is 39891239. The next prime is 39891259. The reversal of 39891242 is 24219893.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 22743361 + 17147881 = 4769^2 + 4141^2 .

It is a super-2 number, since 2×39891242² = 3182622376605128, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 39891196 and 39891205.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9972809 + ... + 9972812.

Almost surely, 2^39891242 is an apocalyptic number.

39891242 is a deficient number, since it is larger than the sum of its proper divisors (19945624).

39891242 is a wasteful number, since it uses less digits than its factorization.

39891242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19945623.

The product of its digits is 31104, while the sum is 38.

The square root of 39891242 is about 6315.9513930999. The cubic root of 39891242 is about 341.6849520520.

The spelling of 39891242 in words is "thirty-nine million, eight hundred ninety-one thousand, two hundred forty-two".