1912121311 has 4 divisors (see below), whose sum is σ = 1943467624. Its totient is φ = 1880775000.

The previous prime is 1912121287. The next prime is 1912121317. The reversal of 1912121311 is 1131212191.

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 1912121311 - 2¹⁵ = 1912088543 is a prime.

It is a super-3 number, since 3×1912121311³ (a number of 29 digits) contains 333 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 (1912121317) 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, 15673065 + ... + 15673186.

It is an arithmetic number, because the mean of its divisors is an integer number (485866906).

Almost surely, 2^1912121311 is an apocalyptic number.

1912121311 is a deficient number, since it is larger than the sum of its proper divisors (31346313).

1912121311 is an equidigital number, since it uses as much as digits as its factorization.

1912121311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31346312.

The product of its digits is 108, while the sum is 22.

The square root of 1912121311 is about 43727.8093551461. The cubic root of 1912121311 is about 1241.1906078818.

The spelling of 1912121311 in words is "one billion, nine hundred twelve million, one hundred twenty-one thousand, three hundred eleven".