21147141 has 4 divisors (see below), whose sum is σ = 28196192. Its totient is φ = 14098092.

The previous prime is 21147127. The next prime is 21147157. The reversal of 21147141 is 14174112.

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 de Polignac number, because none of the positive numbers 2^k-21147141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147241) 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, 3524521 + ... + 3524526.

It is an arithmetic number, because the mean of its divisors is an integer number (7049048).

Almost surely, 2^21147141 is an apocalyptic number.

It is an amenable number.

21147141 is a deficient number, since it is larger than the sum of its proper divisors (7049051).

21147141 is an equidigital number, since it uses as much as digits as its factorization.

21147141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7049050.

The product of its digits is 224, while the sum is 21.

The square root of 21147141 is about 4598.6020701948. The cubic root of 21147141 is about 276.5352849533.

The spelling of 21147141 in words is "twenty-one million, one hundred forty-seven thousand, one hundred forty-one".