21352449 has 4 divisors (see below), whose sum is σ = 28469936. Its totient is φ = 14234964.

The previous prime is 21352423. The next prime is 21352451. The reversal of 21352449 is 94425312.

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 not a de Polignac number, because 21352449 - 2⁵ = 21352417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21352049) 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, 3558739 + ... + 3558744.

It is an arithmetic number, because the mean of its divisors is an integer number (7117484).

Almost surely, 2^21352449 is an apocalyptic number.

It is an amenable number.

21352449 is a deficient number, since it is larger than the sum of its proper divisors (7117487).

21352449 is an equidigital number, since it uses as much as digits as its factorization.

21352449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7117486.

The product of its digits is 8640, while the sum is 30.

The square root of 21352449 is about 4620.8710217880. The cubic root of 21352449 is about 277.4273229041.

The spelling of 21352449 in words is "twenty-one million, three hundred fifty-two thousand, four hundred forty-nine".