21094868197225 has 9 divisors (see below), whose sum is σ = 26157665040663. Its totient is φ = 16875876186120.

The previous prime is 21094868197223. The next prime is 21094868197241. The reversal of 21094868197225 is 52279186849012.

The square root of 21094868197225 is 4592915.

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., 7594152551001 + 13500715646224 = 2755749^2 + 3674332^2 .

It is not a de Polignac number, because 21094868197225 - 2¹ = 21094868197223 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21094868197223) 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, 22505284 + ... + 23423866.

Almost surely, 2^{21094868197225} is an apocalyptic number.

21094868197225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21094868197225 is the 4592915-th square number.

21094868197225 is the 2296458-th centered octagonal number.

It is an amenable number.

21094868197225 is a deficient number, since it is larger than the sum of its proper divisors (5062796843438).

21094868197225 is an frugal number, since it uses more digits than its factorization.

21094868197225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1837176 (or 918588 counting only the distinct ones).

The product of its (nonzero) digits is 34836480, while the sum is 64.

The spelling of 21094868197225 in words is "twenty-one trillion, ninety-four billion, eight hundred sixty-eight million, one hundred ninety-seven thousand, two hundred twenty-five".