21063493 has 16 divisors (see below), whose sum is σ = 24679296. Its totient is φ = 17763840.

The previous prime is 21063481. The next prime is 21063503. The reversal of 21063493 is 39436012.

It is a cyclic number.

It is not a de Polignac number, because 21063493 - 2⁵ = 21063461 is a prime.

It is a super-2 number, since 2×21063493² = 887341474722098, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21063403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12880 + ... + 14422.

It is an arithmetic number, because the mean of its divisors is an integer number (1542456).

Almost surely, 2^21063493 is an apocalyptic number.

It is an amenable number.

21063493 is a deficient number, since it is larger than the sum of its proper divisors (3615803).

21063493 is a wasteful number, since it uses less digits than its factorization.

21063493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1644.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 21063493 is about 4589.4981207099. The cubic root of 21063493 is about 276.1701892659.

The spelling of 21063493 in words is "twenty-one million, sixty-three thousand, four hundred ninety-three".