1984995181 has 4 divisors (see below), whose sum is σ = 2137687132. Its totient is φ = 1832303232.

The previous prime is 1984995179. The next prime is 1984995211. The reversal of 1984995181 is 1815994891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1815994891 = 37 ⋅49080943.

It can be written as a sum of positive squares in 2 ways, for example, as 310957956 + 1674037225 = 17634^2 + 40915^2 .

It is a cyclic number.

It is not a de Polignac number, because 1984995181 - 2¹ = 1984995179 is a prime.

It is a super-2 number, since 2×1984995181² = 7880411737186445522, 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 (1984995101) 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, 76345956 + ... + 76345981.

It is an arithmetic number, because the mean of its divisors is an integer number (534421783).

Almost surely, 2^1984995181 is an apocalyptic number.

It is an amenable number.

1984995181 is a deficient number, since it is larger than the sum of its proper divisors (152691951).

1984995181 is a wasteful number, since it uses less digits than its factorization.

1984995181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152691950.

The product of its digits is 933120, while the sum is 55.

The square root of 1984995181 is about 44553.2847386138. The cubic root of 1984995181 is about 1256.7623227693.

The spelling of 1984995181 in words is "one billion, nine hundred eighty-four million, nine hundred ninety-five thousand, one hundred eighty-one".