1391864920 has 16 divisors (see below), whose sum is σ = 3131696160. Its totient is φ = 556745952.

The previous prime is 1391864917. The next prime is 1391864921. The reversal of 1391864920 is 294681931.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1391864921) 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, 17398272 + ... + 17398351.

It is an arithmetic number, because the mean of its divisors is an integer number (195731010).

Almost surely, 2^1391864920 is an apocalyptic number.

1391864920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1391864920 is an abundant number, since it is smaller than the sum of its proper divisors (1739831240).

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

1391864920 is a wasteful number, since it uses less digits than its factorization.

1391864920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34796634 (or 34796630 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 1391864920 is about 37307.7059064210. The cubic root of 1391864920 is about 1116.5179162766.

The spelling of 1391864920 in words is "one billion, three hundred ninety-one million, eight hundred sixty-four thousand, nine hundred twenty".