21475001 has 2 divisors, whose sum is σ = 21475002. Its totient is φ = 21475000.

The previous prime is 21474991. The next prime is 21475019. The reversal of 21475001 is 10057412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19149376 + 2325625 = 4376^2 + 1525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21475001 is a prime.

It is a super-2 number, since 2×21475001² = 922351335900002, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21475061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10737500 + 10737501.

It is an arithmetic number, because the mean of its divisors is an integer number (10737501).

Almost surely, 2^21475001 is an apocalyptic number.

It is an amenable number.

21475001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21475001 is an equidigital number, since it uses as much as digits as its factorization.

21475001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 21475001 is about 4634.1127521889. The cubic root of 21475001 is about 277.9570737509.

The spelling of 21475001 in words is "twenty-one million, four hundred seventy-five thousand, one".