21292423 has 2 divisors, whose sum is σ = 21292424. Its totient is φ = 21292422.

The previous prime is 21292417. The next prime is 21292429. The reversal of 21292423 is 32429212.

It is a balanced prime because it is at equal distance from previous prime (21292417) and next prime (21292429).

It is a cyclic number.

It is not a de Polignac number, because 21292423 - 2⁵ = 21292391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21292429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10646211 + 10646212.

It is an arithmetic number, because the mean of its divisors is an integer number (10646212).

Almost surely, 2^21292423 is an apocalyptic number.

21292423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21292423 is an equidigital number, since it uses as much as digits as its factorization.

21292423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 21292423 is about 4614.3713548001. The cubic root of 21292423 is about 277.1671110390.

The spelling of 21292423 in words is "twenty-one million, two hundred ninety-two thousand, four hundred twenty-three".