1989262439 has 4 divisors (see below), whose sum is σ = 1994803920. Its totient is φ = 1983720960.

The previous prime is 1989262421. The next prime is 1989262459. The reversal of 1989262439 is 9342629891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9342629891 = 7 ⋅1334661413.

It is a cyclic number.

It is not a de Polignac number, because 1989262439 - 2⁸ = 1989262183 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 (1989262459) 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, 2770202 + ... + 2770919.

It is an arithmetic number, because the mean of its divisors is an integer number (498700980).

Almost surely, 2^1989262439 is an apocalyptic number.

1989262439 is a deficient number, since it is larger than the sum of its proper divisors (5541481).

1989262439 is an equidigital number, since it uses as much as digits as its factorization.

1989262439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5541480.

The product of its digits is 1679616, while the sum is 53.

The square root of 1989262439 is about 44601.1484044974. The cubic root of 1989262439 is about 1257.6622562152.

The spelling of 1989262439 in words is "one billion, nine hundred eighty-nine million, two hundred sixty-two thousand, four hundred thirty-nine".