1616163981 has 8 divisors (see below), whose sum is σ = 2170388640. Its totient is φ = 1069690992.

The previous prime is 1616163961. The next prime is 1616164001. The reversal of 1616163981 is 1893616161.

It is an interprime number because it is at equal distance from previous prime (1616163961) and next prime (1616164001).

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

It is not a de Polignac number, because 1616163981 - 2⁶ = 1616163917 is a prime.

It is a super-2 number, since 2×1616163981² = 5223972026963536722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1616163911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1937430 + ... + 1938263.

It is an arithmetic number, because the mean of its divisors is an integer number (271298580).

Almost surely, 2^1616163981 is an apocalyptic number.

It is an amenable number.

1616163981 is a deficient number, since it is larger than the sum of its proper divisors (554224659).

1616163981 is a wasteful number, since it uses less digits than its factorization.

1616163981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3875835.

The product of its digits is 46656, while the sum is 42.

The square root of 1616163981 is about 40201.5420226638. The cubic root of 1616163981 is about 1173.5325531127.

The spelling of 1616163981 in words is "one billion, six hundred sixteen million, one hundred sixty-three thousand, nine hundred eighty-one".