20021161506 has 16 divisors (see below), whose sum is σ = 40121936064. Its totient is φ = 6660451664.

The previous prime is 20021161483. The next prime is 20021161597. The reversal of 20021161506 is 60516112002.

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, 3313941 + ... + 3319976.

It is an arithmetic number, because the mean of its divisors is an integer number (2507621004).

Almost surely, 2^20021161506 is an apocalyptic number.

20021161506 is an abundant number, since it is smaller than the sum of its proper divisors (20100774558).

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

20021161506 is a wasteful number, since it uses less digits than its factorization.

20021161506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6634425.

The product of its (nonzero) digits is 720, while the sum is 24.

Adding to 20021161506 its reverse (60516112002), we get a palindrome (80537273508).

The spelling of 20021161506 in words is "twenty billion, twenty-one million, one hundred sixty-one thousand, five hundred six".