21479040 has 256 divisors, whose sum is σ = 83721600. Its totient is φ = 5160960.

The previous prime is 21479027. The next prime is 21479057. The reversal of 21479040 is 4097412.

It is a happy number.

It is a super-2 number, since 2×21479040² = 922698318643200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21478995 and 21479013.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 190024 + ... + 190136.

Almost surely, 2^21479040 is an apocalyptic number.

21479040 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 21479040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41860800).

21479040 is an abundant number, since it is smaller than the sum of its proper divisors (62242560).

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

21479040 is a wasteful number, since it uses less digits than its factorization.

21479040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21479040 is about 4634.5485217009. The cubic root of 21479040 is about 277.9744986356.

The spelling of 21479040 in words is "twenty-one million, four hundred seventy-nine thousand, forty".