21393467 has 2 divisors, whose sum is σ = 21393468. Its totient is φ = 21393466.

The previous prime is 21393461. The next prime is 21393481. The reversal of 21393467 is 76439312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21393467 - 2¹⁶ = 21327931 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21393461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10696733 + 10696734.

It is an arithmetic number, because the mean of its divisors is an integer number (10696734).

Almost surely, 2^21393467 is an apocalyptic number.

21393467 is a deficient number, since it is larger than the sum of its proper divisors (1).

21393467 is an equidigital number, since it uses as much as digits as its factorization.

21393467 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 35.

The square root of 21393467 is about 4625.3072330387. The cubic root of 21393467 is about 277.6048549993.

The spelling of 21393467 in words is "twenty-one million, three hundred ninety-three thousand, four hundred sixty-seven".