1213436509 has 2 divisors, whose sum is σ = 1213436510. Its totient is φ = 1213436508.

The previous prime is 1213436467. The next prime is 1213436593. The reversal of 1213436509 is 9056343121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1199583225 + 13853284 = 34635^2 + 3722^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213436509 - 2¹¹ = 1213434461 is a prime.

It is a super-2 number, since 2×1213436509² = 2944856322748214162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1213439509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606718254 + 606718255.

It is an arithmetic number, because the mean of its divisors is an integer number (606718255).

Almost surely, 2^1213436509 is an apocalyptic number.

It is an amenable number.

1213436509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213436509 is an equidigital number, since it uses as much as digits as its factorization.

1213436509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 1213436509 is about 34834.4155828686. The cubic root of 1213436509 is about 1066.6100853559.

The spelling of 1213436509 in words is "one billion, two hundred thirteen million, four hundred thirty-six thousand, five hundred nine".