20011523406 has 64 divisors (see below), whose sum is σ = 48202629120. Its totient is φ = 5410510560.

The previous prime is 20011523393. The next prime is 20011523407. The reversal of 20011523406 is 60432511002.

It is a super-2 number, since 2×20011523406² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011523407) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 713215 + ... + 740741.

It is an arithmetic number, because the mean of its divisors is an integer number (753166080).

Almost surely, 2^20011523406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20011523406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24101314560).

20011523406 is an abundant number, since it is smaller than the sum of its proper divisors (28191105714).

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

20011523406 is a wasteful number, since it uses less digits than its factorization.

20011523406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28469.

The product of its (nonzero) digits is 1440, while the sum is 24.

The spelling of 20011523406 in words is "twenty billion, eleven million, five hundred twenty-three thousand, four hundred six".