21392127 has 8 divisors (see below), whose sum is σ = 31692080. Its totient is φ = 14261400.

The previous prime is 21392123. The next prime is 21392131. The reversal of 21392127 is 72129312.

It is an interprime number because it is at equal distance from previous prime (21392123) and next prime (21392131).

It is not a de Polignac number, because 21392127 - 2² = 21392123 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 792301 = 21392127 / (2 + 1 + 3 + 9 + 2 + 1 + 2 + 7).

It is a Duffinian number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 21392127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21392123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 396124 + ... + 396177.

It is an arithmetic number, because the mean of its divisors is an integer number (3961510).

Almost surely, 2^21392127 is an apocalyptic number.

21392127 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21392127 is a deficient number, since it is larger than the sum of its proper divisors (10299953).

21392127 is an equidigital number, since it uses as much as digits as its factorization.

21392127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792310 (or 792304 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21392127 is about 4625.1623755280. The cubic root of 21392127 is about 277.5990588642.

The spelling of 21392127 in words is "twenty-one million, three hundred ninety-two thousand, one hundred twenty-seven".