21025026 has 24 divisors (see below), whose sum is σ = 49695984. Its totient is φ = 6371160.

The previous prime is 21025021. The next prime is 21025031. The reversal of 21025026 is 62052012.

It is an interprime number because it is at equal distance from previous prime (21025021) and next prime (21025031).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21025021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52896 + ... + 53291.

It is an arithmetic number, because the mean of its divisors is an integer number (2070666).

Almost surely, 2^21025026 is an apocalyptic number.

21025026 is an abundant number, since it is smaller than the sum of its proper divisors (28670958).

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

21025026 is a wasteful number, since it uses less digits than its factorization.

21025026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106206 (or 106203 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 21025026 is about 4585.3054423888. The cubic root of 21025026 is about 276.0019691101.

Adding to 21025026 its reverse (62052012), we get a palindrome (83077038).

It can be divided in two parts, 210250 and 26, that added together give a triangular number (210276 = T₆₄₈).

The spelling of 21025026 in words is "twenty-one million, twenty-five thousand, twenty-six".