21194245 has 8 divisors (see below), whose sum is σ = 25563384. Its totient is φ = 16868544.

The previous prime is 21194237. The next prime is 21194269. The reversal of 21194245 is 54249112.

It can be written as a sum of positive squares in 4 ways, for example, as 6155361 + 15038884 = 2481^2 + 3878^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21194245 - 2³ = 21194237 is a prime.

It is a super-2 number, since 2×21194245² = 898392042240050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9774 + ... + 11743.

It is an arithmetic number, because the mean of its divisors is an integer number (3195423).

Almost surely, 2^21194245 is an apocalyptic number.

It is an amenable number.

21194245 is a deficient number, since it is larger than the sum of its proper divisors (4369139).

21194245 is a wasteful number, since it uses less digits than its factorization.

21194245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21719.

The product of its digits is 2880, while the sum is 28.

The square root of 21194245 is about 4603.7207778057. The cubic root of 21194245 is about 276.7404546659.

The spelling of 21194245 in words is "twenty-one million, one hundred ninety-four thousand, two hundred forty-five".