21242960 has 40 divisors (see below), whose sum is σ = 49791456. Its totient is φ = 8428160.

The previous prime is 21242959. The next prime is 21242971. The reversal of 21242960 is 6924212.

21242960 = T₂₉₅ + T₂₉₆ + ... + T₅₃₄.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9467 + ... + 11493.

Almost surely, 2^21242960 is an apocalyptic number.

21242960 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 21242960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24895728).

21242960 is an abundant number, since it is smaller than the sum of its proper divisors (28548496).

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

21242960 is a wasteful number, since it uses less digits than its factorization.

21242960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2171 (or 2165 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 21242960 is about 4609.0085701808. The cubic root of 21242960 is about 276.9523218560.

The spelling of 21242960 in words is "twenty-one million, two hundred forty-two thousand, nine hundred sixty".