16121431 has 6 divisors (see below), whose sum is σ = 16506960. Its totient is φ = 15744708.

The previous prime is 16121429. The next prime is 16121437. The reversal of 16121431 is 13412161.

It is not a de Polignac number, because 16121431 - 2¹ = 16121429 is a prime.

It is a super-2 number, since 2×16121431² = 519801074975522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16121399 and 16121408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16121437) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2511 + ... + 6208.

It is an arithmetic number, because the mean of its divisors is an integer number (2751160).

Almost surely, 2^16121431 is an apocalyptic number.

16121431 is a deficient number, since it is larger than the sum of its proper divisors (385529).

16121431 is an frugal number, since it uses more digits than its factorization.

16121431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8805 (or 8762 counting only the distinct ones).

The product of its digits is 144, while the sum is 19.

The square root of 16121431 is about 4015.1501839906. The cubic root of 16121431 is about 252.6200768620.

Adding to 16121431 its reverse (13412161), we get a palindrome (29533592).

The spelling of 16121431 in words is "sixteen million, one hundred twenty-one thousand, four hundred thirty-one".