1381705992 has 128 divisors (see below), whose sum is σ = 4062960000. Its totient is φ = 433859328.

The previous prime is 1381705987. The next prime is 1381705999. The reversal of 1381705992 is 2995071831.

It is a super-2 number, since 2×1381705992² = 3818222896657408128, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1381705999) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 807634 + ... + 809342.

It is an arithmetic number, because the mean of its divisors is an integer number (31741875).

Almost surely, 2^1381705992 is an apocalyptic number.

1381705992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1381705992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2031480000).

1381705992 is an abundant number, since it is smaller than the sum of its proper divisors (2681254008).

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

1381705992 is a wasteful number, since it uses less digits than its factorization.

1381705992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1940 (or 1930 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 1381705992 is about 37171.3060303240. The cubic root of 1381705992 is about 1113.7948710510.

The spelling of 1381705992 in words is "one billion, three hundred eighty-one million, seven hundred five thousand, nine hundred ninety-two".