21994467 has 16 divisors (see below), whose sum is σ = 32313600. Its totient is φ = 13196000.

The previous prime is 21994421. The next prime is 21994471. The reversal of 21994467 is 76449912.

It is a cyclic number.

It is not a de Polignac number, because 21994467 - 2⁶ = 21994403 is a prime.

It is a super-2 number, since 2×21994467² = 967513157228178, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21994487) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34 + ... + 6632.

It is an arithmetic number, because the mean of its divisors is an integer number (2019600).

Almost surely, 2^21994467 is an apocalyptic number.

21994467 is a deficient number, since it is larger than the sum of its proper divisors (10319133).

21994467 is a wasteful number, since it uses less digits than its factorization.

21994467 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6714.

The product of its digits is 108864, while the sum is 42.

The square root of 21994467 is about 4689.8259029520. The cubic root of 21994467 is about 280.1804406663.

Subtracting 21994467 from its reverse (76449912), we obtain a palindrome (54455445).

It can be divided in two parts, 2199 and 4467, that added together give a palindrome (6666).

The spelling of 21994467 in words is "twenty-one million, nine hundred ninety-four thousand, four hundred sixty-seven".