21426066 has 32 divisors (see below), whose sum is σ = 47764800. Its totient is φ = 7119360.

The previous prime is 21426059. The next prime is 21426101. The reversal of 21426066 is 66062412.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33106 + ... + 33746.

It is an arithmetic number, because the mean of its divisors is an integer number (1492650).

Almost surely, 2^21426066 is an apocalyptic number.

21426066 is an abundant number, since it is smaller than the sum of its proper divisors (26338734).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21426066 is a wasteful number, since it uses less digits than its factorization.

21426066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1271 (or 1265 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 21426066 is about 4628.8298737370. The cubic root of 21426066 is about 277.7457866210.

Adding to 21426066 its reverse (66062412), we get a palindrome (87488478).

The spelling of 21426066 in words is "twenty-one million, four hundred twenty-six thousand, sixty-six".