21993462 has 24 divisors (see below), whose sum is σ = 48668256. Its totient is φ = 7174896.

The previous prime is 21993437. The next prime is 21993467. The reversal of 21993462 is 26439912.

21993462 is a `hidden beast` number, since 2 + 199 + 3 + 462 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21993467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12153 + ... + 13844.

It is an arithmetic number, because the mean of its divisors is an integer number (2027844).

Almost surely, 2^21993462 is an apocalyptic number.

21993462 is an abundant number, since it is smaller than the sum of its proper divisors (26674794).

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

21993462 is a wasteful number, since it uses less digits than its factorization.

21993462 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26052 (or 26049 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 21993462 is about 4689.7187548935. The cubic root of 21993462 is about 280.1761731440.

The spelling of 21993462 in words is "twenty-one million, nine hundred ninety-three thousand, four hundred sixty-two".