21051201 has 8 divisors (see below), whose sum is σ = 28973824. Its totient is φ = 13581360.

The previous prime is 21051197. The next prime is 21051203. The reversal of 21051201 is 10215012.

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

It is not a de Polignac number, because 21051201 - 2² = 21051197 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21051203) 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, 113086 + ... + 113271.

It is an arithmetic number, because the mean of its divisors is an integer number (3621728).

Almost surely, 2^21051201 is an apocalyptic number.

It is an amenable number.

21051201 is a deficient number, since it is larger than the sum of its proper divisors (7922623).

21051201 is a wasteful number, since it uses less digits than its factorization.

21051201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226391.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 21051201 is about 4588.1587810362. The cubic root of 21051201 is about 276.1164573655.

Adding to 21051201 its reverse (10215012), we get a palindrome (31266213).

The spelling of 21051201 in words is "twenty-one million, fifty-one thousand, two hundred one".