21148097 has 4 divisors (see below), whose sum is σ = 21157296. Its totient is φ = 21138900.

The previous prime is 21148079. The next prime is 21148123. The reversal of 21148097 is 79084112.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21148097 - 2⁶ = 21148033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21148067) 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, 2222 + ... + 6872.

It is an arithmetic number, because the mean of its divisors is an integer number (5289324).

Almost surely, 2^21148097 is an apocalyptic number.

It is an amenable number.

21148097 is a deficient number, since it is larger than the sum of its proper divisors (9199).

21148097 is an equidigital number, since it uses as much as digits as its factorization.

21148097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9198.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 21148097 is about 4598.7060136521. The cubic root of 21148097 is about 276.5394520059.

The spelling of 21148097 in words is "twenty-one million, one hundred forty-eight thousand, ninety-seven".