1366901989 has 4 divisors (see below), whose sum is σ = 1403845324. Its totient is φ = 1329958656.

The previous prime is 1366901957. The next prime is 1366902001. The reversal of 1366901989 is 9891096631.

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 1127952225 + 238949764 = 33585^2 + 15458^2 .

It is a cyclic number.

It is not a de Polignac number, because 1366901989 - 2⁵ = 1366901957 is a prime.

It is a super-2 number, since 2×1366901989² = 3736842095064312242, 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 (1366901909) 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, 18471612 + ... + 18471685.

It is an arithmetic number, because the mean of its divisors is an integer number (350961331).

Almost surely, 2^1366901989 is an apocalyptic number.

It is an amenable number.

1366901989 is a deficient number, since it is larger than the sum of its proper divisors (36943335).

1366901989 is an equidigital number, since it uses as much as digits as its factorization.

1366901989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36943334.

The product of its (nonzero) digits is 629856, while the sum is 52.

The square root of 1366901989 is about 36971.6376294045. The cubic root of 1366901989 is about 1109.8027377186.

The spelling of 1366901989 in words is "one billion, three hundred sixty-six million, nine hundred one thousand, nine hundred eighty-nine".