21270097 has 4 divisors (see below), whose sum is σ = 21297136. Its totient is φ = 21243060.

The previous prime is 21270089. The next prime is 21270113. The reversal of 21270097 is 79007212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21270097 - 2³ = 21270089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21270017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12303 + ... + 13924.

It is an arithmetic number, because the mean of its divisors is an integer number (5324284).

Almost surely, 2^21270097 is an apocalyptic number.

It is an amenable number.

21270097 is a deficient number, since it is larger than the sum of its proper divisors (27039).

21270097 is an equidigital number, since it uses as much as digits as its factorization.

21270097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27038.

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 21270097 is about 4611.9515392077. The cubic root of 21270097 is about 277.0702033740.

The spelling of 21270097 in words is "twenty-one million, two hundred seventy thousand, ninety-seven".