15640546820 has 48 divisors (see below), whose sum is σ = 32986926000. Its totient is φ = 6229278720.

The previous prime is 15640546813. The next prime is 15640546849. The reversal of 15640546820 is 2864504651.

15640546820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 113891584 + 15526655236 = 10672^2 + 124606^2 .

It is a super-2 number, since 2×15640546820² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 5108090 + ... + 5111150.

It is an arithmetic number, because the mean of its divisors is an integer number (687227625).

Almost surely, 2^15640546820 is an apocalyptic number.

15640546820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15640546820 is an abundant number, since it is smaller than the sum of its proper divisors (17346379180).

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

15640546820 is a wasteful number, since it uses less digits than its factorization.

15640546820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4088 (or 4086 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 41.

The spelling of 15640546820 in words is "fifteen billion, six hundred forty million, five hundred forty-six thousand, eight hundred twenty".