21432601 has 2 divisors, whose sum is σ = 21432602. Its totient is φ = 21432600.

The previous prime is 21432599. The next prime is 21432629. The reversal of 21432601 is 10623412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21206025 + 226576 = 4605^2 + 476^2 .

It is a cyclic number.

It is not a de Polignac number, because 21432601 - 2¹ = 21432599 is a prime.

Together with 21432599, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21432661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716300 + 10716301.

It is an arithmetic number, because the mean of its divisors is an integer number (10716301).

Almost surely, 2^21432601 is an apocalyptic number.

It is an amenable number.

21432601 is a deficient number, since it is larger than the sum of its proper divisors (1).

21432601 is an equidigital number, since it uses as much as digits as its factorization.

21432601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 21432601 is about 4629.5357218624. The cubic root of 21432601 is about 277.7740214544.

The spelling of 21432601 in words is "twenty-one million, four hundred thirty-two thousand, six hundred one".