21346572 has 48 divisors (see below), whose sum is σ = 53994080. Its totient is φ = 6524928.

The previous prime is 21346571. The next prime is 21346573. The reversal of 21346572 is 27564312.

It is an interprime number because it is at equal distance from previous prime (21346571) and next prime (21346573).

It is a super-2 number, since 2×21346572² = 911352272302368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21346571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29754 + ... + 30462.

Almost surely, 2^21346572 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21346572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26997040).

21346572 is an abundant number, since it is smaller than the sum of its proper divisors (32647508).

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

21346572 is a wasteful number, since it uses less digits than its factorization.

21346572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 922 (or 920 counting only the distinct ones).

The product of its digits is 10080, while the sum is 30.

The square root of 21346572 is about 4620.2350589553. The cubic root of 21346572 is about 277.4018677446.

The spelling of 21346572 in words is "twenty-one million, three hundred forty-six thousand, five hundred seventy-two".