1226689687 has 4 divisors (see below), whose sum is σ = 1246799416. Its totient is φ = 1206579960.

The previous prime is 1226689679. The next prime is 1226689697. The reversal of 1226689687 is 7869866221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7869866221 = 7 ⋅1124266603.

It is a cyclic number.

It is not a de Polignac number, because 1226689687 - 2³ = 1226689679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1226689627) 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, 10054773 + ... + 10054894.

It is an arithmetic number, because the mean of its divisors is an integer number (311699854).

Almost surely, 2^1226689687 is an apocalyptic number.

1226689687 is a deficient number, since it is larger than the sum of its proper divisors (20109729).

1226689687 is an equidigital number, since it uses as much as digits as its factorization.

1226689687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20109728.

The product of its digits is 3483648, while the sum is 55.

The square root of 1226689687 is about 35024.1300677119. The cubic root of 1226689687 is about 1070.4792120802.

It can be divided in two parts, 122668 and 9687, that added together give a triangular number (132355 = T₅₁₄).

The spelling of 1226689687 in words is "one billion, two hundred twenty-six million, six hundred eighty-nine thousand, six hundred eighty-seven".