21692141 has 4 divisors (see below), whose sum is σ = 21709884. Its totient is φ = 21674400.

The previous prime is 21692137. The next prime is 21692161. The reversal of 21692141 is 14129612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8940100 + 12752041 = 2990^2 + 3571^2 .

It is a cyclic number.

It is not a de Polignac number, because 21692141 - 2² = 21692137 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21692141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21692161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6890 + ... + 9531.

It is an arithmetic number, because the mean of its divisors is an integer number (5427471).

Almost surely, 2^21692141 is an apocalyptic number.

It is an amenable number.

21692141 is a deficient number, since it is larger than the sum of its proper divisors (17743).

21692141 is a wasteful number, since it uses less digits than its factorization.

21692141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17742.

The product of its digits is 864, while the sum is 26.

The square root of 21692141 is about 4657.4822597622. The cubic root of 21692141 is about 278.8907688523.

The spelling of 21692141 in words is "twenty-one million, six hundred ninety-two thousand, one hundred forty-one".