21471746 has 8 divisors (see below), whose sum is σ = 32292864. Its totient is φ = 10707460.

The previous prime is 21471743. The next prime is 21471757. The reversal of 21471746 is 64717412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21471746² = 922071752577032, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21471743) 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, 13250 + ... + 14781.

It is an arithmetic number, because the mean of its divisors is an integer number (4036608).

Almost surely, 2^21471746 is an apocalyptic number.

21471746 is a deficient number, since it is larger than the sum of its proper divisors (10821118).

21471746 is a wasteful number, since it uses less digits than its factorization.

21471746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28416.

The product of its digits is 9408, while the sum is 32.

The square root of 21471746 is about 4633.7615389659. The cubic root of 21471746 is about 277.9430295763.

It can be divided in two parts, 2 and 1471746, that multiplied together give a palindrome (2943492).

The spelling of 21471746 in words is "twenty-one million, four hundred seventy-one thousand, seven hundred forty-six".