21370001 has 2 divisors, whose sum is σ = 21370002. Its totient is φ = 21370000.

The previous prime is 21369991. The next prime is 21370009. The reversal of 21370001 is 10007312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17850625 + 3519376 = 4225^2 + 1876^2 .

It is a cyclic number.

It is not a de Polignac number, because 21370001 - 2⁶ = 21369937 is a prime.

It is not a weakly prime, because it can be changed into another prime (21370009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10685000 + 10685001.

It is an arithmetic number, because the mean of its divisors is an integer number (10685001).

Almost surely, 2^21370001 is an apocalyptic number.

It is an amenable number.

21370001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21370001 is an equidigital number, since it uses as much as digits as its factorization.

21370001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 21370001 is about 4622.7698406908. The cubic root of 21370001 is about 277.5033184139.

Adding to 21370001 its reverse (10007312), we get a palindrome (31377313).

The spelling of 21370001 in words is "twenty-one million, three hundred seventy thousand, one".