21194773 has 2 divisors, whose sum is σ = 21194774. Its totient is φ = 21194772.

The previous prime is 21194689. The next prime is 21194777. The reversal of 21194773 is 37749112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20277009 + 917764 = 4503^2 + 958^2 .

It is a cyclic number.

It is not a de Polignac number, because 21194773 - 2¹⁷ = 21063701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21194777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10597386 + 10597387.

It is an arithmetic number, because the mean of its divisors is an integer number (10597387).

Almost surely, 2^21194773 is an apocalyptic number.

It is an amenable number.

21194773 is a deficient number, since it is larger than the sum of its proper divisors (1).

21194773 is an equidigital number, since it uses as much as digits as its factorization.

21194773 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 34.

The square root of 21194773 is about 4603.7781223686. The cubic root of 21194773 is about 276.7427527386.

The spelling of 21194773 in words is "twenty-one million, one hundred ninety-four thousand, seven hundred seventy-three".