16561454420 has 24 divisors (see below), whose sum is σ = 39747490944. Its totient is φ = 5678212896.

The previous prime is 16561454407. The next prime is 16561454453. The reversal of 16561454420 is 2445416561.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59147912 + ... + 59148191.

It is an arithmetic number, because the mean of its divisors is an integer number (1656145456).

Almost surely, 2^16561454420 is an apocalyptic number.

16561454420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16561454420 is an abundant number, since it is smaller than the sum of its proper divisors (23186036524).

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

16561454420 is a wasteful number, since it uses less digits than its factorization.

16561454420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118296119 (or 118296117 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 38.

The spelling of 16561454420 in words is "sixteen billion, five hundred sixty-one million, four hundred fifty-four thousand, four hundred twenty".