39928789 has 4 divisors (see below), whose sum is σ = 40340524. Its totient is φ = 39517056.

The previous prime is 39928739. The next prime is 39928799. The reversal of 39928789 is 98782993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98782993 = 5189 ⋅19037.

It can be written as a sum of positive squares in 2 ways, for example, as 5904900 + 34023889 = 2430^2 + 5833^2 .

It is a cyclic number.

It is not a de Polignac number, because 39928789 - 2¹³ = 39920597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39928739) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205722 + ... + 205915.

It is an arithmetic number, because the mean of its divisors is an integer number (10085131).

Almost surely, 2^39928789 is an apocalyptic number.

It is an amenable number.

39928789 is a deficient number, since it is larger than the sum of its proper divisors (411735).

39928789 is an equidigital number, since it uses as much as digits as its factorization.

39928789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411734.

The product of its digits is 1959552, while the sum is 55.

The square root of 39928789 is about 6318.9230886283. The cubic root of 39928789 is about 341.7921202861.

The spelling of 39928789 in words is "thirty-nine million, nine hundred twenty-eight thousand, seven hundred eighty-nine".