1640400553920 has 56 divisors (see below), whose sum is σ = 5208271761744. Its totient is φ = 437440147456.

The previous prime is 1640400553861. The next prime is 1640400553933. The reversal of 1640400553920 is 293550040461.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 854374329 + ... + 854376248.

Almost surely, 2^{1640400553920} is an apocalyptic number.

1640400553920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1640400553920 is an abundant number, since it is smaller than the sum of its proper divisors (3567871207824).

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

1640400553920 is a wasteful number, since it uses less digits than its factorization.

1640400553920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1708750597 (or 1708750587 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 39.

The spelling of 1640400553920 in words is "one trillion, six hundred forty billion, four hundred million, five hundred fifty-three thousand, nine hundred twenty".