21472872 has 32 divisors (see below), whose sum is σ = 53930400.
Its totient is φ = 7124544.
The previous prime is 21472849. The next prime is 21472879. The reversal of 21472872 is 27827412.
It is a super-2 number, since 2×214728722 = 922168463856768, which contains 22 as substring.
It is not an unprimeable number, because it can be changed into a prime (21472879) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3543 + ... + 7449.
It is an arithmetic number, because the mean of its divisors is an integer number (1685325).
Almost surely, 221472872 is an apocalyptic number.
It is an amenable number.
21472872 is an abundant number, since it is smaller than the sum of its proper divisors (32457528).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21472872 is a wasteful number, since it uses less digits than its factorization.
21472872 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 4145 (or 4141 counting only the distinct ones).
The product of its digits is 12544, while the sum is 33.
The square root of 21472872 is about 4633.8830369357.
The cubic root of 21472872 is about 277.9478880289.
The spelling of 21472872 in words is "twenty-one million, four hundred seventy-two thousand, eight hundred seventy-two".