21375001 has 16 divisors (see below), whose sum is σ = 23639040. Its totient is φ = 19237120.

The previous prime is 21374971. The next prime is 21375007. The reversal of 21375001 is 10057312.

It is a cyclic number.

It is not a de Polignac number, because 21375001 - 2¹³ = 21366809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21375001.

It is not an unprimeable number, because it can be changed into a prime (21375007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94050 + ... + 94276.

It is an arithmetic number, because the mean of its divisors is an integer number (1477440).

Almost surely, 2^21375001 is an apocalyptic number.

It is an amenable number.

21375001 is a deficient number, since it is larger than the sum of its proper divisors (2264039).

21375001 is a wasteful number, since it uses less digits than its factorization.

21375001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464.

The product of its (nonzero) digits is 210, while the sum is 19.

The square root of 21375001 is about 4623.3106103743. The cubic root of 21375001 is about 277.5249594735.

The spelling of 21375001 in words is "twenty-one million, three hundred seventy-five thousand, one".