1261321692 has 12 divisors (see below), whose sum is σ = 2943083976. Its totient is φ = 420440560.

The previous prime is 1261321651. The next prime is 1261321697. The reversal of 1261321692 is 2961231621.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261321697) 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, 52555059 + ... + 52555082.

It is an arithmetic number, because the mean of its divisors is an integer number (245256998).

Almost surely, 2^1261321692 is an apocalyptic number.

1261321692 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1261321692 is an abundant number, since it is smaller than the sum of its proper divisors (1681762284).

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

1261321692 is a wasteful number, since it uses less digits than its factorization.

1261321692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105110148 (or 105110146 counting only the distinct ones).

The product of its digits is 7776, while the sum is 33.

The square root of 1261321692 is about 35515.0910459202. The cubic root of 1261321692 is about 1080.4598213452.

The spelling of 1261321692 in words is "one billion, two hundred sixty-one million, three hundred twenty-one thousand, six hundred ninety-two".