21402527 has 2 divisors, whose sum is σ = 21402528. Its totient is φ = 21402526.

The previous prime is 21402523. The next prime is 21402587. The reversal of 21402527 is 72520412.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21402527 - 2² = 21402523 is a prime.

It is a Chen prime.

It is equal to p_1353821 and since 21402527 and 1353821 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21402523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701263 + 10701264.

It is an arithmetic number, because the mean of its divisors is an integer number (10701264).

Almost surely, 2^21402527 is an apocalyptic number.

21402527 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402527 is an equidigital number, since it uses as much as digits as its factorization.

21402527 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 21402527 is about 4626.2865237683. The cubic root of 21402527 is about 277.6440374442.

Adding to 21402527 its reverse (72520412), we get a palindrome (93922939).

The spelling of 21402527 in words is "twenty-one million, four hundred two thousand, five hundred twenty-seven".