21153941 has 2 divisors, whose sum is σ = 21153942. Its totient is φ = 21153940.

The previous prime is 21153931. The next prime is 21153947. The reversal of 21153941 is 14935112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15171025 + 5982916 = 3895^2 + 2446^2 .

It is a cyclic number.

It is not a de Polignac number, because 21153941 - 2⁶ = 21153877 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21153941.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21153947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576970 + 10576971.

It is an arithmetic number, because the mean of its divisors is an integer number (10576971).

Almost surely, 2^21153941 is an apocalyptic number.

It is an amenable number.

21153941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21153941 is an equidigital number, since it uses as much as digits as its factorization.

21153941 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 26.

The square root of 21153941 is about 4599.3413658914. The cubic root of 21153941 is about 276.5649223468.

The spelling of 21153941 in words is "twenty-one million, one hundred fifty-three thousand, nine hundred forty-one".