162641981 has 4 divisors (see below), whose sum is σ = 162752700. Its totient is φ = 162531264.

The previous prime is 162641977. The next prime is 162641987. The reversal of 162641981 is 189146261.

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

It can be written as a sum of positive squares in 2 ways, for example, as 85729081 + 76912900 = 9259^2 + 8770^2 .

It is a cyclic number.

It is not a de Polignac number, because 162641981 - 2² = 162641977 is a prime.

It is a super-2 number, since 2×162641981² = 52904827967208722, 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 (162641987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53126 + ... + 56103.

It is an arithmetic number, because the mean of its divisors is an integer number (40688175).

Almost surely, 2^162641981 is an apocalyptic number.

It is an amenable number.

162641981 is a deficient number, since it is larger than the sum of its proper divisors (110719).

162641981 is a wasteful number, since it uses less digits than its factorization.

162641981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110718.

The product of its digits is 20736, while the sum is 38.

The square root of 162641981 is about 12753.1165210704. The cubic root of 162641981 is about 545.8553255764.

The spelling of 162641981 in words is "one hundred sixty-two million, six hundred forty-one thousand, nine hundred eighty-one".