21485761 has 8 divisors (see below), whose sum is σ = 23789664. Its totient is φ = 19240320.

The previous prime is 21485747. The next prime is 21485771. The reversal of 21485761 is 16758412.

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

It is not a de Polignac number, because 21485761 - 2⁵ = 21485729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21485701) 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, 13840 + ... + 15313.

It is an arithmetic number, because the mean of its divisors is an integer number (2973708).

Almost surely, 2^21485761 is an apocalyptic number.

It is an amenable number.

21485761 is a deficient number, since it is larger than the sum of its proper divisors (2303903).

21485761 is a wasteful number, since it uses less digits than its factorization.

21485761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29231.

The product of its digits is 13440, while the sum is 34.

The square root of 21485761 is about 4635.2735625851. The cubic root of 21485761 is about 278.0034892511.

The spelling of 21485761 in words is "twenty-one million, four hundred eighty-five thousand, seven hundred sixty-one".