21540801 has 8 divisors (see below), whose sum is σ = 28778080. Its totient is φ = 14332032.

The previous prime is 21540797. The next prime is 21540817. The reversal of 21540801 is 10804512.

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

It is not a de Polignac number, because 21540801 - 2² = 21540797 is a prime.

It is a super-2 number, since 2×21540801² = 928012215443202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21540901) 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, 5296 + ... + 8433.

It is an arithmetic number, because the mean of its divisors is an integer number (3597260).

Almost surely, 2^21540801 is an apocalyptic number.

It is an amenable number.

21540801 is a deficient number, since it is larger than the sum of its proper divisors (7237279).

21540801 is a wasteful number, since it uses less digits than its factorization.

21540801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14255.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 21540801 is about 4641.2068473620. The cubic root of 21540801 is about 278.2406736952.

The spelling of 21540801 in words is "twenty-one million, five hundred forty thousand, eight hundred one".