1933996781 has 4 divisors (see below), whose sum is σ = 1934088864. Its totient is φ = 1933904700.

The previous prime is 1933996777. The next prime is 1933996819. The reversal of 1933996781 is 1876993391.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1933996781 - 2² = 1933996777 is a prime.

It is a super-2 number, since 2×1933996781² = 7480687097836723922, 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 (1933996711) 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, 2576 + ... + 62246.

It is an arithmetic number, because the mean of its divisors is an integer number (483522216).

Almost surely, 2^1933996781 is an apocalyptic number.

It is an amenable number.

1933996781 is a deficient number, since it is larger than the sum of its proper divisors (92083).

1933996781 is an equidigital number, since it uses as much as digits as its factorization.

1933996781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92082.

The product of its digits is 2204496, while the sum is 56.

The square root of 1933996781 is about 43977.2302561223. The cubic root of 1933996781 is about 1245.9059187183.

The spelling of 1933996781 in words is "one billion, nine hundred thirty-three million, nine hundred ninety-six thousand, seven hundred eighty-one".