1261722941 has 4 divisors (see below), whose sum is σ = 1274730492. Its totient is φ = 1248715392.

The previous prime is 1261722901. The next prime is 1261722961. The reversal of 1261722941 is 1492271621.

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 775344025 + 486378916 = 27845^2 + 22054^2 .

It is a cyclic number.

It is not a de Polignac number, because 1261722941 - 2²² = 1257528637 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 (1261722901) 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 3 ways as a sum of consecutive naturals, for example, 6503630 + ... + 6503823.

It is an arithmetic number, because the mean of its divisors is an integer number (318682623).

Almost surely, 2^1261722941 is an apocalyptic number.

It is an amenable number.

1261722941 is a deficient number, since it is larger than the sum of its proper divisors (13007551).

1261722941 is an equidigital number, since it uses as much as digits as its factorization.

1261722941 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13007550.

The product of its digits is 12096, while the sum is 35.

The square root of 1261722941 is about 35520.7395897101. The cubic root of 1261722941 is about 1080.5743803992.

The spelling of 1261722941 in words is "one billion, two hundred sixty-one million, seven hundred twenty-two thousand, nine hundred forty-one".