16391481 has 8 divisors (see below), whose sum is σ = 22446144. Its totient is φ = 10632240.

The previous prime is 16391477. The next prime is 16391489. The reversal of 16391481 is 18419361.

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

It is not a de Polignac number, because 16391481 - 2² = 16391477 is a prime.

It is a super-2 number, since 2×16391481² = 537361298746722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (16391489) 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, 73725 + ... + 73946.

It is an arithmetic number, because the mean of its divisors is an integer number (2805768).

Almost surely, 2^16391481 is an apocalyptic number.

It is an amenable number.

16391481 is a deficient number, since it is larger than the sum of its proper divisors (6054663).

16391481 is a wasteful number, since it uses less digits than its factorization.

16391481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147711.

The product of its digits is 5184, while the sum is 33.

The square root of 16391481 is about 4048.6394010828. The cubic root of 16391481 is about 254.0228191622.

The spelling of 16391481 in words is "sixteen million, three hundred ninety-one thousand, four hundred eighty-one".