20011989450 has 48 divisors (see below), whose sum is σ = 52549136640. Its totient is φ = 5022616320.

The previous prime is 20011989443. The next prime is 20011989451. The reversal of 20011989450 is 5498911002.

It is a super-2 number, since 2×20011989450² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20011989399 and 20011989408.

It is not an unprimeable number, because it can be changed into a prime (20011989451) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3921370 + ... + 3926469.

It is an arithmetic number, because the mean of its divisors is an integer number (1094773680).

Almost surely, 2^20011989450 is an apocalyptic number.

20011989450 is an abundant number, since it is smaller than the sum of its proper divisors (32537147190).

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

20011989450 is a wasteful number, since it uses less digits than its factorization.

20011989450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7847871 (or 7847866 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 39.

The spelling of 20011989450 in words is "twenty billion, eleven million, nine hundred eighty-nine thousand, four hundred fifty".