21485491 has 8 divisors (see below), whose sum is σ = 22445280. Its totient is φ = 20540352.

The previous prime is 21485489. The next prime is 21485507. The reversal of 21485491 is 19458412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21485491 - 2¹ = 21485489 is a prime.

It is a super-2 number, since 2×21485491² = 923252647022162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21485291) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 610 + ... + 6583.

It is an arithmetic number, because the mean of its divisors is an integer number (2805660).

Almost surely, 2^21485491 is an apocalyptic number.

21485491 is a deficient number, since it is larger than the sum of its proper divisors (959789).

21485491 is a wasteful number, since it uses less digits than its factorization.

21485491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7325.

The product of its digits is 11520, while the sum is 34.

The square root of 21485491 is about 4635.2444379989. The cubic root of 21485491 is about 278.0023247395.

The spelling of 21485491 in words is "twenty-one million, four hundred eighty-five thousand, four hundred ninety-one".