21764496 has 60 divisors (see below), whose sum is σ = 60905328. Its totient is φ = 6694272.

The previous prime is 21764489. The next prime is 21764497. The reversal of 21764496 is 69446712.

It is a happy number.

It is a super-2 number, since 2×21764496² = 947386572268032, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (21764497) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6771 + ... + 9453.

Almost surely, 2^21764496 is an apocalyptic number.

21764496 is a gapful number since it is divisible by the number (26) 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 21764496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30452664).

21764496 is an abundant number, since it is smaller than the sum of its proper divisors (39140832).

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

21764496 is a wasteful number, since it uses less digits than its factorization.

21764496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2720 (or 2701 counting only the distinct ones).

The product of its digits is 72576, while the sum is 39.

The square root of 21764496 is about 4665.2434020102. The cubic root of 21764496 is about 279.2005084788.

The spelling of 21764496 in words is "twenty-one million, seven hundred sixty-four thousand, four hundred ninety-six".