16227981 has 24 divisors (see below), whose sum is σ = 29225664. Its totient is φ = 8429760.

The previous prime is 16227977. The next prime is 16227989. The reversal of 16227981 is 18972261.

It is not a de Polignac number, because 16227981 - 2² = 16227977 is a prime.

It is a super-2 number, since 2×16227981² = 526694734672722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16227989) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11016 + ... + 12401.

It is an arithmetic number, because the mean of its divisors is an integer number (1217736).

Almost surely, 2^16227981 is an apocalyptic number.

16227981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16227981 is a deficient number, since it is larger than the sum of its proper divisors (12997683).

16227981 is a wasteful number, since it uses less digits than its factorization.

16227981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23441 (or 23438 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 16227981 is about 4028.3968275233. The cubic root of 16227981 is about 253.1753953615.

The spelling of 16227981 in words is "sixteen million, two hundred twenty-seven thousand, nine hundred eighty-one".