15643830640 has 40 divisors (see below), whose sum is σ = 36968178528. Its totient is φ = 6154947840.

The previous prime is 15643830619. The next prime is 15643830641. The reversal of 15643830640 is 4603834651.

15643830640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 15643830593 and 15643830602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15643830641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1597972 + ... + 1607731.

Almost surely, 2^15643830640 is an apocalyptic number.

15643830640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15643830640 is an abundant number, since it is smaller than the sum of its proper divisors (21324347888).

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

15643830640 is a wasteful number, since it uses less digits than its factorization.

15643830640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3205777 (or 3205771 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 40.

The spelling of 15643830640 in words is "fifteen billion, six hundred forty-three million, eight hundred thirty thousand, six hundred forty".