20981232801 has 27 divisors (see below), whose sum is σ = 30922773427. Its totient is φ = 13708509360.

The previous prime is 20981232773. The next prime is 20981232859. The reversal of 20981232801 is 10823218902.

The square root of 20981232801 is 144849.

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., 15125310225 + 5855922576 = 122985^2 + 76524^2 .

It is not a de Polignac number, because 20981232801 - 2⁷ = 20981232673 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20981232101) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 23030536 + ... + 23031446.

Almost surely, 2^20981232801 is an apocalyptic number.

20981232801 is the 144849-th square number.

20981232801 is the 72425-th centered octagonal number.

It is an amenable number.

20981232801 is a deficient number, since it is larger than the sum of its proper divisors (9941540626).

20981232801 is an frugal number, since it uses more digits than its factorization.

20981232801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1934 (or 967 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

Multiplying 20981232801 by its sum of digits (36), we get a square (755324380836 = 869094²).

The spelling of 20981232801 in words is "twenty billion, nine hundred eighty-one million, two hundred thirty-two thousand, eight hundred one".