21047401 has 2 divisors, whose sum is σ = 21047402. Its totient is φ = 21047400.

The previous prime is 21047393. The next prime is 21047407. The reversal of 21047401 is 10474012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19360000 + 1687401 = 4400^2 + 1299^2 .

It is a cyclic number.

It is not a de Polignac number, because 21047401 - 2³ = 21047393 is a prime.

It is not a weakly prime, because it can be changed into another prime (21047407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10523700 + 10523701.

It is an arithmetic number, because the mean of its divisors is an integer number (10523701).

Almost surely, 2^21047401 is an apocalyptic number.

It is an amenable number.

21047401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21047401 is an equidigital number, since it uses as much as digits as its factorization.

21047401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 21047401 is about 4587.7446528768. The cubic root of 21047401 is about 276.0998422299.

The spelling of 21047401 in words is "twenty-one million, forty-seven thousand, four hundred one".