20191288620 has 96 divisors (see below), whose sum is σ = 60410750400. Its totient is φ = 5021097984.

The previous prime is 20191288589. The next prime is 20191288643. The reversal of 20191288620 is 2688219102.

It is a super-2 number, since 2×20191288620² (a number of 21 digits) contains 22 as substring.

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, 20376 + ... + 201984.

It is an arithmetic number, because the mean of its divisors is an integer number (629278650).

Almost surely, 2^20191288620 is an apocalyptic number.

20191288620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20191288620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30205375200).

20191288620 is an abundant number, since it is smaller than the sum of its proper divisors (40219461780).

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

20191288620 is a wasteful number, since it uses less digits than its factorization.

20191288620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181747 (or 181745 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 39.

The spelling of 20191288620 in words is "twenty billion, one hundred ninety-one million, two hundred eighty-eight thousand, six hundred twenty".