20869684672225 has 27 divisors (see below), whose sum is σ = 26377423639833. Its totient is φ = 16379783415840.

The previous prime is 20869684672219. The next prime is 20869684672231. The reversal of 20869684672225 is 52227648696802.

The square root of 20869684672225 is 4568335.

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

It is an interprime number because it is at equal distance from previous prime (20869684672219) and next prime (20869684672231).

It can be written as a sum of positive squares in 4 ways, for example, as 157209871009 + 20712474801216 = 396497^2 + 4551096^2 .

It is not a de Polignac number, because 20869684672225 - 2¹⁵ = 20869684639457 is a prime.

It is a super-4 number, since 4×20869684672225⁴ (a number of 54 digits) contains 4444 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1210600156 + ... + 1210617394.

Almost surely, 2^{20869684672225} is an apocalyptic number.

20869684672225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20869684672225 is the 4568335-th square number.

20869684672225 is the 2284168-th centered octagonal number.

It is an amenable number.

20869684672225 is a deficient number, since it is larger than the sum of its proper divisors (5507738967608).

20869684672225 is an frugal number, since it uses more digits than its factorization.

20869684672225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34594 (or 17297 counting only the distinct ones).

The product of its (nonzero) digits is 278691840, while the sum is 67.

The spelling of 20869684672225 in words is "twenty trillion, eight hundred sixty-nine billion, six hundred eighty-four million, six hundred seventy-two thousand, two hundred twenty-five".