1993889771 has 4 divisors (see below), whose sum is σ = 2005029000. Its totient is φ = 1982750544.

The previous prime is 1993889743. The next prime is 1993889813. The reversal of 1993889771 is 1779883991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1779883991 = 743 ⋅2395537.

It is a cyclic number.

It is not a de Polignac number, because 1993889771 - 2²² = 1989695467 is a prime.

It is a super-3 number, since 3×1993889771³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1993889701) 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, 5569346 + ... + 5569703.

It is an arithmetic number, because the mean of its divisors is an integer number (501257250).

Almost surely, 2^1993889771 is an apocalyptic number.

1993889771 is a deficient number, since it is larger than the sum of its proper divisors (11139229).

1993889771 is a wasteful number, since it uses less digits than its factorization.

1993889771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11139228.

The product of its digits is 6858432, while the sum is 62.

The square root of 1993889771 is about 44652.9928560225. The cubic root of 1993889771 is about 1258.6366733436.

The spelling of 1993889771 in words is "one billion, nine hundred ninety-three million, eight hundred eighty-nine thousand, seven hundred seventy-one".