1213656113 has 4 divisors (see below), whose sum is σ = 1213921380. Its totient is φ = 1213390848.

The previous prime is 1213656091. The next prime is 1213656131. The reversal of 1213656113 is 3116563121.

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 575184289 + 638471824 = 23983^2 + 25268^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213656113 - 2⁶ = 1213656049 is a prime.

It is a super-2 number, since 2×1213656113² = 2945922321244537538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1213656173) 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, 125648 + ... + 134961.

It is an arithmetic number, because the mean of its divisors is an integer number (303480345).

Almost surely, 2^1213656113 is an apocalyptic number.

It is an amenable number.

1213656113 is a deficient number, since it is larger than the sum of its proper divisors (265267).

1213656113 is an equidigital number, since it uses as much as digits as its factorization.

1213656113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265266.

The product of its digits is 3240, while the sum is 29.

The square root of 1213656113 is about 34837.5675528588. The cubic root of 1213656113 is about 1066.6744254101.

The spelling of 1213656113 in words is "one billion, two hundred thirteen million, six hundred fifty-six thousand, one hundred thirteen".