21425526 has 32 divisors (see below), whose sum is σ = 49152000. Its totient is φ = 6910920.

The previous prime is 21425501. The next prime is 21425533. The reversal of 21425526 is 62552412.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21425526.

It is a congruent 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, 4726 + ... + 8073.

It is an arithmetic number, because the mean of its divisors is an integer number (1536000).

Almost surely, 2^21425526 is an apocalyptic number.

21425526 is an abundant number, since it is smaller than the sum of its proper divisors (27726474).

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

21425526 is a wasteful number, since it uses less digits than its factorization.

21425526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12841 (or 12835 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 21425526 is about 4628.7715432931. The cubic root of 21425526 is about 277.7434532639.

Adding to 21425526 its reverse (62552412), we get a palindrome (83977938).

The spelling of 21425526 in words is "twenty-one million, four hundred twenty-five thousand, five hundred twenty-six".