21425055 has 16 divisors (see below), whose sum is σ = 35462880. Its totient is φ = 11032448.

The previous prime is 21425023. The next prime is 21425057. The reversal of 21425055 is 55052412.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21425055 - 2⁵ = 21425023 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21425057) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24192 + ... + 25061.

It is an arithmetic number, because the mean of its divisors is an integer number (2216430).

Almost surely, 2^21425055 is an apocalyptic number.

21425055 is a deficient number, since it is larger than the sum of its proper divisors (14037825).

21425055 is a wasteful number, since it uses less digits than its factorization.

21425055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49290.

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 21425055 is about 4628.7206655835. The cubic root of 21425055 is about 277.7414180261.

Adding to 21425055 its reverse (55052412), we get a palindrome (76477467).

The spelling of 21425055 in words is "twenty-one million, four hundred twenty-five thousand, fifty-five".