21402467 has 2 divisors, whose sum is σ = 21402468. Its totient is φ = 21402466.

The previous prime is 21402419. The next prime is 21402481. The reversal of 21402467 is 76420412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21402467 - 2¹² = 21398371 is a prime.

It is not a weakly prime, because it can be changed into another prime (21402967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701233 + 10701234.

It is an arithmetic number, because the mean of its divisors is an integer number (10701234).

Almost surely, 2^21402467 is an apocalyptic number.

21402467 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402467 is an equidigital number, since it uses as much as digits as its factorization.

21402467 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 21402467 is about 4626.2800390811. The cubic root of 21402467 is about 277.6437779942.

Adding to 21402467 its reverse (76420412), we get a palindrome (97822879).

The spelling of 21402467 in words is "twenty-one million, four hundred two thousand, four hundred sixty-seven".