20271779641 has 9 divisors (see below), whose sum is σ = 20414439759. Its totient is φ = 20130112536.

The previous prime is 20271779639. The next prime is 20271779651. The reversal of 20271779641 is 14697717202.

The square root of 20271779641 is 142379.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 18440282025 + 1831497616 = 135795^2 + 42796^2 .

It is not a de Polignac number, because 20271779641 - 2¹ = 20271779639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20271779591 and 20271779600.

It is not an unprimeable number, because it can be changed into a prime (20271779651) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24631156 + ... + 24631978.

Almost surely, 2^20271779641 is an apocalyptic number.

20271779641 is the 142379-th square number.

20271779641 is the 71190-th centered octagonal number.

It is an amenable number.

20271779641 is a deficient number, since it is larger than the sum of its proper divisors (142660118).

20271779641 is an frugal number, since it uses more digits than its factorization.

20271779641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1992 (or 996 counting only the distinct ones).

The product of its (nonzero) digits is 296352, while the sum is 46.

The spelling of 20271779641 in words is "twenty billion, two hundred seventy-one million, seven hundred seventy-nine thousand, six hundred forty-one".