21472140 has 48 divisors (see below), whose sum is σ = 60812640. Its totient is φ = 5660160.

The previous prime is 21472127. The next prime is 21472163. The reversal of 21472140 is 4127412.

It is a happy number.

It is a super-2 number, since 2×21472140² = 922105592359200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3330 + ... + 7350.

It is an arithmetic number, because the mean of its divisors is an integer number (1266930).

Almost surely, 2^21472140 is an apocalyptic number.

21472140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21472140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30406320).

21472140 is an abundant number, since it is smaller than the sum of its proper divisors (39340500).

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

21472140 is a wasteful number, since it uses less digits than its factorization.

21472140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4122 (or 4120 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 21472140 is about 4633.8040528274. The cubic root of 21472140 is about 277.9447296226.

Adding to 21472140 its reverse (4127412), we get a palindrome (25599552).

It can be divided in two parts, 21472 and 140, that added together give a palindrome (21612).

The spelling of 21472140 in words is "twenty-one million, four hundred seventy-two thousand, one hundred forty".