21298464 has 168 divisors, whose sum is σ = 69409872. Its totient is φ = 6376320.

The previous prime is 21298447. The next prime is 21298471. The reversal of 21298464 is 46489212.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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 27 ways as a sum of consecutive naturals, for example, 256567 + ... + 256649.

It is an arithmetic number, because the mean of its divisors is an integer number (413154).

Almost surely, 2^21298464 is an apocalyptic number.

21298464 is a gapful number since it is divisible by the number (24) 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 21298464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34704936).

21298464 is an abundant number, since it is smaller than the sum of its proper divisors (48111408).

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

21298464 is an equidigital number, since it uses as much as digits as its factorization.

21298464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 99 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 21298464 is about 4615.0258937518. The cubic root of 21298464 is about 277.1933208038.

It can be divided in two parts, 2 and 1298464, that added together give a triangular number (1298466 = T₁₆₁₁).

The spelling of 21298464 in words is "twenty-one million, two hundred ninety-eight thousand, four hundred sixty-four".