21494970 has 160 divisors (see below), whose sum is σ = 70253568. Its totient is φ = 4603392.

The previous prime is 21494959. The next prime is 21494999. The reversal of 21494970 is 7949412.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 96279 + ... + 96501.

Almost surely, 2^21494970 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21494970, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35126784).

21494970 is an abundant number, since it is smaller than the sum of its proper divisors (48758598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21494970 is a wasteful number, since it uses less digits than its factorization.

21494970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 257 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 21494970 is about 4636.2668171709. The cubic root of 21494970 is about 278.0432018846.

The spelling of 21494970 in words is "twenty-one million, four hundred ninety-four thousand, nine hundred seventy".