1138950661 has 4 divisors (see below), whose sum is σ = 1139254732. Its totient is φ = 1138646592.

The previous prime is 1138950641. The next prime is 1138950679. The reversal of 1138950661 is 1660598311.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 93721761 + 1045228900 = 9681^2 + 32330^2 .

It is a cyclic number.

It is not a de Polignac number, because 1138950661 - 2⁵ = 1138950629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1138950641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146346 + ... + 153931.

It is an arithmetic number, because the mean of its divisors is an integer number (284813683).

Almost surely, 2^1138950661 is an apocalyptic number.

It is an amenable number.

1138950661 is a deficient number, since it is larger than the sum of its proper divisors (304071).

1138950661 is an equidigital number, since it uses as much as digits as its factorization.

1138950661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304070.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 1138950661 is about 33748.3430852538. The cubic root of 1138950661 is about 1044.3233063188.

The spelling of 1138950661 in words is "one billion, one hundred thirty-eight million, nine hundred fifty thousand, six hundred sixty-one".