20416531640 has 96 divisors (see below), whose sum is σ = 46984860000. Its totient is φ = 7984304640.

The previous prime is 20416531637. The next prime is 20416531703. The reversal of 20416531640 is 4613561402.

It is a junction number, because it is equal to n+sod(n) for n = 20416531597 and 20416531606.

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, 34084061 + ... + 34084659.

It is an arithmetic number, because the mean of its divisors is an integer number (489425625).

Almost surely, 2^20416531640 is an apocalyptic number.

20416531640 is a gapful number since it is divisible by the number (20) 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 20416531640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23492430000).

20416531640 is an abundant number, since it is smaller than the sum of its proper divisors (26568328360).

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

20416531640 is a wasteful number, since it uses less digits than its factorization.

20416531640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961 (or 896 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 32.

The spelling of 20416531640 in words is "twenty billion, four hundred sixteen million, five hundred thirty-one thousand, six hundred forty".