21430855 has 8 divisors (see below), whose sum is σ = 26604000. Its totient is φ = 16553376.

The previous prime is 21430847. The next prime is 21430859. The reversal of 21430855 is 55803412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21430855 - 2³ = 21430847 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21430859) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73755 + ... + 74044.

It is an arithmetic number, because the mean of its divisors is an integer number (3325500).

Almost surely, 2^21430855 is an apocalyptic number.

21430855 is a deficient number, since it is larger than the sum of its proper divisors (5173145).

21430855 is a wasteful number, since it uses less digits than its factorization.

21430855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147833.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 21430855 is about 4629.3471461968. The cubic root of 21430855 is about 277.7664783256.

The spelling of 21430855 in words is "twenty-one million, four hundred thirty thousand, eight hundred fifty-five".