16400031 has 8 divisors (see below), whose sum is σ = 22067760. Its totient is φ = 10832832.

The previous prime is 16400017. The next prime is 16400047. The reversal of 16400031 is 13000461.

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

It is not a de Polignac number, because 16400031 - 2⁶ = 16399967 is a prime.

It is a super-2 number, since 2×16400031² = 537922033601922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16400231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24750 + ... + 25403.

It is an arithmetic number, because the mean of its divisors is an integer number (2758470).

Almost surely, 2^16400031 is an apocalyptic number.

16400031 is a deficient number, since it is larger than the sum of its proper divisors (5667729).

16400031 is a wasteful number, since it uses less digits than its factorization.

16400031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50265.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 16400031 is about 4049.6951737137. The cubic root of 16400031 is about 254.0669786371.

Adding to 16400031 its reverse (13000461), we get a palindrome (29400492).

The spelling of 16400031 in words is "sixteen million, four hundred thousand, thirty-one".