1392187989 has 4 divisors (see below), whose sum is σ = 1856250656. Its totient is φ = 928125324.

The previous prime is 1392187981. The next prime is 1392187991. The reversal of 1392187989 is 9897812931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1392187989 - 2³ = 1392187981 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 (1392187981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 232031329 + ... + 232031334.

It is an arithmetic number, because the mean of its divisors is an integer number (464062664).

Almost surely, 2^1392187989 is an apocalyptic number.

It is an amenable number.

1392187989 is a deficient number, since it is larger than the sum of its proper divisors (464062667).

1392187989 is an equidigital number, since it uses as much as digits as its factorization.

1392187989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464062666.

The product of its digits is 1959552, while the sum is 57.

The square root of 1392187989 is about 37312.0354443442. The cubic root of 1392187989 is about 1116.6042954495.

The spelling of 1392187989 in words is "one billion, three hundred ninety-two million, one hundred eighty-seven thousand, nine hundred eighty-nine".