1640140920 has 128 divisors (see below), whose sum is σ = 5964192000. Its totient is φ = 397607040.

The previous prime is 1640140903. The next prime is 1640140937. The reversal of 1640140920 is 290410461.

1640140920 is a `hidden beast` number, since 1 + 640 + 14 + 0 + 9 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1640140903) and next prime (1640140937).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 57150 + ... + 80909.

It is an arithmetic number, because the mean of its divisors is an integer number (46595250).

Almost surely, 2^1640140920 is an apocalyptic number.

1640140920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1640140920 is an abundant number, since it is smaller than the sum of its proper divisors (4324051080).

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

1640140920 is a wasteful number, since it uses less digits than its factorization.

1640140920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138090 (or 138080 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 1640140920 is about 40498.6533109436. The cubic root of 1640140920 is about 1179.3074841102.

The spelling of 1640140920 in words is "one billion, six hundred forty million, one hundred forty thousand, nine hundred twenty".