21494090 has 8 divisors (see below), whose sum is σ = 38689380. Its totient is φ = 8597632.

The previous prime is 21494071. The next prime is 21494101. The reversal of 21494090 is 9049412.

It can be written as a sum of positive squares in 2 ways, for example, as 18774889 + 2719201 = 4333^2 + 1649^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1074695 + ... + 1074714.

Almost surely, 2^21494090 is an apocalyptic number.

21494090 is a deficient number, since it is larger than the sum of its proper divisors (17195290).

21494090 is a wasteful number, since it uses less digits than its factorization.

21494090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2149416.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 21494090 is about 4636.1719122569. The cubic root of 21494090 is about 278.0394074874.

The spelling of 21494090 in words is "twenty-one million, four hundred ninety-four thousand, ninety".