21422331 has 12 divisors (see below), whose sum is σ = 35363952. Its totient is φ = 12241296.

The previous prime is 21422327. The next prime is 21422341. The reversal of 21422331 is 13322412.

It is not a de Polignac number, because 21422331 - 2² = 21422327 is a prime.

It is a super-2 number, since 2×21422331² = 917832530947122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21422321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 169956 + ... + 170081.

It is an arithmetic number, because the mean of its divisors is an integer number (2946996).

Almost surely, 2^21422331 is an apocalyptic number.

21422331 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21422331 is a deficient number, since it is larger than the sum of its proper divisors (13941621).

21422331 is a wasteful number, since it uses less digits than its factorization.

21422331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340050 (or 340047 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 21422331 is about 4628.4264064582. The cubic root of 21422331 is about 277.7296467659.

Adding to 21422331 its reverse (13322412), we get a palindrome (34744743).

The spelling of 21422331 in words is "twenty-one million, four hundred twenty-two thousand, three hundred thirty-one".