20011770972 has 72 divisors (see below), whose sum is σ = 52373521200. Its totient is φ = 6435168768.

The previous prime is 20011770953. The next prime is 20011770973. The reversal of 20011770972 is 27907711002.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011770973) 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, 1346679 + ... + 1361457.

Almost surely, 2^20011770972 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20011770972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26186760600).

20011770972 is an abundant number, since it is smaller than the sum of its proper divisors (32361750228).

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

20011770972 is a wasteful number, since it uses less digits than its factorization.

20011770972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16115 (or 16110 counting only the distinct ones).

The product of its (nonzero) digits is 12348, while the sum is 36.

The spelling of 20011770972 in words is "twenty billion, eleven million, seven hundred seventy thousand, nine hundred seventy-two".