1838780161 has 9 divisors (see below), whose sum is σ = 1858236681. Its totient is φ = 1819526592.

The previous prime is 1838780143. The next prime is 1838780171. The reversal of 1838780161 is 1610878381.

The square root of 1838780161 is 42881.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 616578561 + 1222201600 = 24831^2 + 34960^2 .

It is not a de Polignac number, because 1838780161 - 2⁷ = 1838780033 is a prime.

It is a super-2 number, since 2×1838780161² = 6762224960974371842, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1838780101) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5874541 + ... + 5874853.

Almost surely, 2^1838780161 is an apocalyptic number.

1838780161 is the 42881-st square number.

1838780161 is the 21441-st centered octagonal number.

It is an amenable number.

1838780161 is a deficient number, since it is larger than the sum of its proper divisors (19456520).

1838780161 is an frugal number, since it uses more digits than its factorization.

1838780161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The cubic root of 1838780161 is about 1225.1142830489.

The spelling of 1838780161 in words is "one billion, eight hundred thirty-eight million, seven hundred eighty thousand, one hundred sixty-one".