21063407 has 6 divisors (see below), whose sum is σ = 21218472. Its totient is φ = 20909172.

The previous prime is 21063403. The next prime is 21063451. The reversal of 21063407 is 70436012.

It is not a de Polignac number, because 21063407 - 2² = 21063403 is a prime.

It is a super-2 number, since 2×21063407² = 887334228895298, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21063403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 74288 + ... + 74570.

It is an arithmetic number, because the mean of its divisors is an integer number (3536412).

Almost surely, 2^21063407 is an apocalyptic number.

21063407 is a deficient number, since it is larger than the sum of its proper divisors (155065).

21063407 is an frugal number, since it uses more digits than its factorization.

21063407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829 (or 546 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 21063407 is about 4589.4887514842. The cubic root of 21063407 is about 276.1698134076.

Adding to 21063407 its reverse (70436012), we get a palindrome (91499419).

The spelling of 21063407 in words is "twenty-one million, sixty-three thousand, four hundred seven".