20516610042 has 64 divisors (see below), whose sum is σ = 46349233920. Its totient is φ = 6810143040.

The previous prime is 20516610013. The next prime is 20516610071. The reversal of 20516610042 is 24001661502.

20516610042 is a `hidden beast` number, since 2 + 0 + 5 + 1 + 6 + 610 + 0 + 42 = 666.

It is an interprime number because it is at equal distance from previous prime (20516610013) and next prime (20516610071).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 20516609988 and 20516610015.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1044403 + ... + 1063865.

It is an arithmetic number, because the mean of its divisors is an integer number (724206780).

Almost surely, 2^20516610042 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20516610042, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23174616960).

20516610042 is an abundant number, since it is smaller than the sum of its proper divisors (25832623878).

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

20516610042 is an equidigital number, since it uses as much as digits as its factorization.

20516610042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19727 (or 19709 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The spelling of 20516610042 in words is "twenty billion, five hundred sixteen million, six hundred ten thousand, forty-two".