1154781638 has 4 divisors (see below), whose sum is σ = 1732172460. Its totient is φ = 577390818.

The previous prime is 1154781599. The next prime is 1154781703. The reversal of 1154781638 is 8361874511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8361874511 = 859 ⋅9734429.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 288695408 + ... + 288695411.

It is an arithmetic number, because the mean of its divisors is an integer number (433043115).

Almost surely, 2^1154781638 is an apocalyptic number.

1154781638 is a deficient number, since it is larger than the sum of its proper divisors (577390822).

1154781638 is an equidigital number, since it uses as much as digits as its factorization.

1154781638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577390821.

The product of its digits is 161280, while the sum is 44.

The square root of 1154781638 is about 33982.0781883628. The cubic root of 1154781638 is about 1049.1396241451.

The spelling of 1154781638 in words is "one billion, one hundred fifty-four million, seven hundred eighty-one thousand, six hundred thirty-eight".