21714145 has 4 divisors (see below), whose sum is σ = 26056980. Its totient is φ = 17371312.

The previous prime is 21714137. The next prime is 21714149. The reversal of 21714145 is 54141712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15872256 + 5841889 = 3984^2 + 2417^2 .

It is a cyclic number.

It is not a de Polignac number, because 21714145 - 2³ = 21714137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21714149) 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, 2171410 + ... + 2171419.

It is an arithmetic number, because the mean of its divisors is an integer number (6514245).

Almost surely, 2^21714145 is an apocalyptic number.

It is an amenable number.

21714145 is a deficient number, since it is larger than the sum of its proper divisors (4342835).

21714145 is an equidigital number, since it uses as much as digits as its factorization.

21714145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4342834.

The product of its digits is 1120, while the sum is 25.

The square root of 21714145 is about 4659.8438815050. The cubic root of 21714145 is about 278.9850370739.

Adding to 21714145 its reverse (54141712), we get a palindrome (75855857).

The spelling of 21714145 in words is "twenty-one million, seven hundred fourteen thousand, one hundred forty-five".