21026494 has 8 divisors (see below), whose sum is σ = 32557248. Its totient is φ = 10174080.

The previous prime is 21026477. The next prime is 21026497. The reversal of 21026494 is 49462012.

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

It is a super-2 number, since 2×21026494² = 884226899864072, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21026497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169507 + ... + 169630.

It is an arithmetic number, because the mean of its divisors is an integer number (4069656).

Almost surely, 2^21026494 is an apocalyptic number.

21026494 is a deficient number, since it is larger than the sum of its proper divisors (11530754).

21026494 is a wasteful number, since it uses less digits than its factorization.

21026494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 339170.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 21026494 is about 4585.4655161717. The cubic root of 21026494 is about 276.0083925894.

The spelling of 21026494 in words is "twenty-one million, twenty-six thousand, four hundred ninety-four".