1143923781 has 64 divisors (see below), whose sum is σ = 2061029376. Its totient is φ = 545011200.

The previous prime is 1143923779. The next prime is 1143923843. The reversal of 1143923781 is 1873293411.

It is not a de Polignac number, because 1143923781 - 2¹ = 1143923779 is a prime.

It is a super-2 number, since 2×1143923781² = 2617123233474671922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1143923771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 500361 + ... + 502641.

It is an arithmetic number, because the mean of its divisors is an integer number (32203584).

Almost surely, 2^1143923781 is an apocalyptic number.

1143923781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1143923781 is a deficient number, since it is larger than the sum of its proper divisors (917105595).

1143923781 is a wasteful number, since it uses less digits than its factorization.

1143923781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2482.

The product of its digits is 36288, while the sum is 39.

The square root of 1143923781 is about 33821.9423008200. The cubic root of 1143923781 is about 1045.8410789322.

The spelling of 1143923781 in words is "one billion, one hundred forty-three million, nine hundred twenty-three thousand, seven hundred eighty-one".