20389269681 has 27 divisors (see below), whose sum is σ = 32379427353. Its totient is φ = 12354277320.

The previous prime is 20389269661. The next prime is 20389269697. The reversal of 20389269681 is 18696298302.

The square root of 20389269681 is 142791.

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

It is not a de Polignac number, because 20389269681 - 2²⁷ = 20255051953 is a prime.

It is a super-2 number, since 2×20389269681² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20389269601) 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, 4709940 + ... + 4714266.

Almost surely, 2^20389269681 is an apocalyptic number.

20389269681 is the 142791-st square number.

20389269681 is the 71396-th centered octagonal number.

It is an amenable number.

20389269681 is a deficient number, since it is larger than the sum of its proper divisors (11990157672).

20389269681 is an frugal number, since it uses more digits than its factorization.

20389269681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8682 (or 4341 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 20389269681 in words is "twenty billion, three hundred eighty-nine million, two hundred sixty-nine thousand, six hundred eighty-one".