1261649276664 has 32 divisors (see below), whose sum is σ = 3604712219520. Its totient is φ = 360471221856.

The previous prime is 1261649276621. The next prime is 1261649276669. The reversal of 1261649276664 is 4666729461621.

It is a junction number, because it is equal to n+sod(n) for n = 1261649276598 and 1261649276607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261649276669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3754908394 + ... + 3754908729.

It is an arithmetic number, because the mean of its divisors is an integer number (112647256860).

Almost surely, 2^{1261649276664} is an apocalyptic number.

1261649276664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1261649276664 is an abundant number, since it is smaller than the sum of its proper divisors (2343062942856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261649276664 is a wasteful number, since it uses less digits than its factorization.

1261649276664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7509817139 (or 7509817135 counting only the distinct ones).

The product of its digits is 31352832, while the sum is 60.

The spelling of 1261649276664 in words is "one trillion, two hundred sixty-one billion, six hundred forty-nine million, two hundred seventy-six thousand, six hundred sixty-four".