1213712291 has 4 divisors (see below), whose sum is σ = 1324049784. Its totient is φ = 1103374800.

The previous prime is 1213712273. The next prime is 1213712327. The reversal of 1213712291 is 1922173121.

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

It is not a de Polignac number, because 1213712291 - 2²⁶ = 1146603427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1213712251) 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, 55168730 + ... + 55168751.

It is an arithmetic number, because the mean of its divisors is an integer number (331012446).

Almost surely, 2^1213712291 is an apocalyptic number.

1213712291 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1213712291 is a deficient number, since it is larger than the sum of its proper divisors (110337493).

1213712291 is a wasteful number, since it uses less digits than its factorization.

1213712291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110337492.

The product of its digits is 1512, while the sum is 29.

The square root of 1213712291 is about 34838.3738282946. The cubic root of 1213712291 is about 1066.6908833152.

The spelling of 1213712291 in words is "one billion, two hundred thirteen million, seven hundred twelve thousand, two hundred ninety-one".