1640289657636 has 144 divisors (see below), whose sum is σ = 4759442082304. Its totient is φ = 466598631168.

The previous prime is 1640289657613. The next prime is 1640289657649. The reversal of 1640289657636 is 6367569820461.

1640289657636 is a `hidden beast` number, since 1 + 6 + 4 + 0 + 28 + 9 + 6 + 576 + 36 = 666.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 56678226 + ... + 56707158.

It is a 1-persistent number, because it is pandigital, but 2⋅1640289657636 = 3280579315272 is not.

Almost surely, 2^{1640289657636} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1640289657636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2379721041152).

1640289657636 is an abundant number, since it is smaller than the sum of its proper divisors (3119152424668).

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

1640289657636 is a wasteful number, since it uses less digits than its factorization.

1640289657636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29930 (or 29925 counting only the distinct ones).

The product of its (nonzero) digits is 78382080, while the sum is 63.

The spelling of 1640289657636 in words is "one trillion, six hundred forty billion, two hundred eighty-nine million, six hundred fifty-seven thousand, six hundred thirty-six".