21472847 has 16 divisors (see below), whose sum is σ = 24554880. Its totient is φ = 18597600.

The previous prime is 21472817. The next prime is 21472849. The reversal of 21472847 is 74827412.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21472847 - 2⁶ = 21472783 is a prime.

It is a super-2 number, since 2×21472847² = 922166316570818, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21472849) 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, 26072 + ... + 26882.

It is an arithmetic number, because the mean of its divisors is an integer number (1534680).

Almost surely, 2^21472847 is an apocalyptic number.

21472847 is a deficient number, since it is larger than the sum of its proper divisors (3082033).

21472847 is a wasteful number, since it uses less digits than its factorization.

21472847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934.

The product of its digits is 25088, while the sum is 35.

The square root of 21472847 is about 4633.8803394132. The cubic root of 21472847 is about 277.9477801610.

It can be divided in two parts, 2147 and 2847, that added together give a palindrome (4994).

The spelling of 21472847 in words is "twenty-one million, four hundred seventy-two thousand, eight hundred forty-seven".