21494236 has 24 divisors (see below), whose sum is σ = 39513600. Its totient is φ = 10210992.

The previous prime is 21494233. The next prime is 21494243. The reversal of 21494236 is 63249412.

It is a happy number.

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 21494198 and 21494207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21494233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14665 + ... + 16063.

It is an arithmetic number, because the mean of its divisors is an integer number (1646400).

Almost surely, 2^21494236 is an apocalyptic number.

It is an amenable number.

21494236 is a deficient number, since it is larger than the sum of its proper divisors (18019364).

21494236 is a wasteful number, since it uses less digits than its factorization.

21494236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593 (or 1591 counting only the distinct ones).

The product of its digits is 10368, while the sum is 31.

The square root of 21494236 is about 4636.1876579793. The cubic root of 21494236 is about 278.0400370196.

The spelling of 21494236 in words is "twenty-one million, four hundred ninety-four thousand, two hundred thirty-six".