21947468 has 12 divisors (see below), whose sum is σ = 38479560. Its totient is φ = 10953312.

The previous prime is 21947467. The next prime is 21947479. The reversal of 21947468 is 86474912.

It is a super-2 number, since 2×21947468² = 963382703222048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21947467) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2546 + ... + 7097.

It is an arithmetic number, because the mean of its divisors is an integer number (3206630).

Almost surely, 2^21947468 is an apocalyptic number.

It is an amenable number.

21947468 is a deficient number, since it is larger than the sum of its proper divisors (16532092).

21947468 is a wasteful number, since it uses less digits than its factorization.

21947468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10216 (or 10214 counting only the distinct ones).

The product of its digits is 96768, while the sum is 41.

The square root of 21947468 is about 4684.8124829069. The cubic root of 21947468 is about 279.9807299664.

The spelling of 21947468 in words is "twenty-one million, nine hundred forty-seven thousand, four hundred sixty-eight".