1212931361991 has 8 divisors (see below), whose sum is σ = 1673008775280. Its totient is φ = 780737428352.

The previous prime is 1212931361987. The next prime is 1212931362001. The reversal of 1212931361991 is 1991631392121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1212931361991 - 2² = 1212931361987 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1212931361991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212931361491) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6970869810 + ... + 6970869983.

It is an arithmetic number, because the mean of its divisors is an integer number (209126096910).

Almost surely, 2^{1212931361991} is an apocalyptic number.

1212931361991 is a deficient number, since it is larger than the sum of its proper divisors (460077413289).

1212931361991 is a wasteful number, since it uses less digits than its factorization.

1212931361991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13941739825.

The product of its digits is 157464, while the sum is 48.

The spelling of 1212931361991 in words is "one trillion, two hundred twelve billion, nine hundred thirty-one million, three hundred sixty-one thousand, nine hundred ninety-one".