21372041 has 2 divisors, whose sum is σ = 21372042. Its totient is φ = 21372040.

The previous prime is 21372031. The next prime is 21372047. The reversal of 21372041 is 14027312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20976400 + 395641 = 4580^2 + 629^2 .

It is a cyclic number.

It is not a de Polignac number, because 21372041 - 2¹⁴ = 21355657 is a prime.

It is not a weakly prime, because it can be changed into another prime (21372047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10686020 + 10686021.

It is an arithmetic number, because the mean of its divisors is an integer number (10686021).

Almost surely, 2^21372041 is an apocalyptic number.

It is an amenable number.

21372041 is a deficient number, since it is larger than the sum of its proper divisors (1).

21372041 is an equidigital number, since it uses as much as digits as its factorization.

21372041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21372041 is about 4622.9904823610. The cubic root of 21372041 is about 277.5121483738.

Adding to 21372041 its reverse (14027312), we get a palindrome (35399353).

The spelling of 21372041 in words is "twenty-one million, three hundred seventy-two thousand, forty-one".