21431027 has 8 divisors (see below), whose sum is σ = 21928320. Its totient is φ = 20937280.

The previous prime is 21431023. The next prime is 21431057. The reversal of 21431027 is 72013412.

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 21431027 - 2² = 21431023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21431023) 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, 14174 + ... + 15612.

It is an arithmetic number, because the mean of its divisors is an integer number (2741040).

Almost surely, 2^21431027 is an apocalyptic number.

21431027 is a deficient number, since it is larger than the sum of its proper divisors (497293).

21431027 is a wasteful number, since it uses less digits than its factorization.

21431027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1773.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21431027 is about 4629.3657232930. The cubic root of 21431027 is about 277.7672214240.

Adding to 21431027 its reverse (72013412), we get a palindrome (93444439).

The spelling of 21431027 in words is "twenty-one million, four hundred thirty-one thousand, twenty-seven".