1389640524 has 24 divisors (see below), whose sum is σ = 3330130608. Its totient is φ = 450694080.

The previous prime is 1389640489. The next prime is 1389640529. The reversal of 1389640524 is 4250469831.

It is a super-2 number, since 2×1389640524² = 3862201571885989152, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1389640529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1564467 + ... + 1565354.

It is an arithmetic number, because the mean of its divisors is an integer number (138755442).

Almost surely, 2^1389640524 is an apocalyptic number.

It is an amenable number.

1389640524 is an abundant number, since it is smaller than the sum of its proper divisors (1940490084).

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

1389640524 is a wasteful number, since it uses less digits than its factorization.

1389640524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3129865 (or 3129863 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The square root of 1389640524 is about 37277.8825042410. The cubic root of 1389640524 is about 1115.9228148979.

The spelling of 1389640524 in words is "one billion, three hundred eighty-nine million, six hundred forty thousand, five hundred twenty-four".