1391585940 has 48 divisors (see below), whose sum is σ = 4329380160. Its totient is φ = 371089440.

The previous prime is 1391585849. The next prime is 1391585941. The reversal of 1391585940 is 495851931.

1391585940 is a `hidden beast` number, since 1 + 3 + 9 + 1 + 58 + 594 + 0 = 666.

It is a super-2 number, since 2×1391585940² = 3873022856811367200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1391585941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1287966 + ... + 1289045.

It is an arithmetic number, because the mean of its divisors is an integer number (90195420).

Almost surely, 2^1391585940 is an apocalyptic number.

1391585940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1391585940 is an abundant number, since it is smaller than the sum of its proper divisors (2937794220).

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

1391585940 is a wasteful number, since it uses less digits than its factorization.

1391585940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2577029 (or 2577021 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The square root of 1391585940 is about 37303.9668131956. The cubic root of 1391585940 is about 1116.4433144535.

The spelling of 1391585940 in words is "one billion, three hundred ninety-one million, five hundred eighty-five thousand, nine hundred forty".