1616149991 has 4 divisors (see below), whose sum is σ = 1622295312. Its totient is φ = 1610004672.

The previous prime is 1616149987. The next prime is 1616150017. The reversal of 1616149991 is 1999416161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1616149991 - 2² = 1616149987 is a prime.

It is a super-2 number, since 2×1616149991² = 5223881586818600162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1616140991) 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 3 ways as a sum of consecutive naturals, for example, 3072266 + ... + 3072791.

It is an arithmetic number, because the mean of its divisors is an integer number (405573828).

Almost surely, 2^1616149991 is an apocalyptic number.

1616149991 is a deficient number, since it is larger than the sum of its proper divisors (6145321).

1616149991 is an equidigital number, since it uses as much as digits as its factorization.

1616149991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6145320.

The product of its digits is 104976, while the sum is 47.

The square root of 1616149991 is about 40201.3680239864. The cubic root of 1616149991 is about 1173.5291669531.

The spelling of 1616149991 in words is "one billion, six hundred sixteen million, one hundred forty-nine thousand, nine hundred ninety-one".