1640545632 has 144 divisors (see below), whose sum is σ = 5208211008. Its totient is φ = 485533440.

The previous prime is 1640545607. The next prime is 1640545657. The reversal of 1640545632 is 2365450461.

1640545632 is a `hidden beast` number, since 1 + 6 + 40 + 54 + 563 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (1640545607) and next prime (1640545657).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 130203 + ... + 142245.

It is an arithmetic number, because the mean of its divisors is an integer number (36168132).

Almost surely, 2^1640545632 is an apocalyptic number.

1640545632 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 1640545632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2604105504).

1640545632 is an abundant number, since it is smaller than the sum of its proper divisors (3567665376).

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

1640545632 is a wasteful number, since it uses less digits than its factorization.

1640545632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12113 (or 12102 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 1640545632 is about 40503.6496133373. The cubic root of 1640545632 is about 1179.4044759059.

The spelling of 1640545632 in words is "one billion, six hundred forty million, five hundred forty-five thousand, six hundred thirty-two".