21455030 has 32 divisors (see below), whose sum is σ = 39813120. Its totient is φ = 8320480.

The previous prime is 21455023. The next prime is 21455033. The reversal of 21455030 is 3055412.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21454993 and 21455011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21455033) 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, 89651 + ... + 89889.

It is an arithmetic number, because the mean of its divisors is an integer number (1244160).

Almost surely, 2^21455030 is an apocalyptic number.

21455030 is a deficient number, since it is larger than the sum of its proper divisors (18358090).

21455030 is a wasteful number, since it uses less digits than its factorization.

21455030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484.

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 21455030 is about 4631.9574695802. The cubic root of 21455030 is about 277.8708835744.

The spelling of 21455030 in words is "twenty-one million, four hundred fifty-five thousand, thirty".