1361683991 has 4 divisors (see below), whose sum is σ = 1363281192. Its totient is φ = 1360086792.

The previous prime is 1361683987. The next prime is 1361683993. The reversal of 1361683991 is 1993861631.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1361683991 - 2² = 1361683987 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1361683993) 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, 797321 + ... + 799026.

It is an arithmetic number, because the mean of its divisors is an integer number (340820298).

Almost surely, 2^1361683991 is an apocalyptic number.

1361683991 is a deficient number, since it is larger than the sum of its proper divisors (1597201).

1361683991 is an equidigital number, since it uses as much as digits as its factorization.

1361683991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597200.

The product of its digits is 209952, while the sum is 47.

The square root of 1361683991 is about 36901.0025744559. The cubic root of 1361683991 is about 1108.3887536511.

The spelling of 1361683991 in words is "one billion, three hundred sixty-one million, six hundred eighty-three thousand, nine hundred ninety-one".