261328614743720 has 32 divisors (see below), whose sum is σ = 588047205839400. Its totient is φ = 104521166312448.

The previous prime is 261328614743719. The next prime is 261328614743731. The reversal of 261328614743720 is 27347416823162.

It can be written as a sum of positive squares in 4 ways, for example, as 259655001626596 + 1673613117124 = 16113814^2 + 1293682^2 .

It is a super-2 number, since 2×261328614743720² (a number of 30 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 320825189 + ... + 321638708.

Almost surely, 2^{261328614743720} is an apocalyptic number.

261328614743720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261328614743720 is an abundant number, since it is smaller than the sum of its proper divisors (326718591095680).

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

261328614743720 is a wasteful number, since it uses less digits than its factorization.

261328614743720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642474077 (or 642474073 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 56.

The spelling of 261328614743720 in words is "two hundred sixty-one trillion, three hundred twenty-eight billion, six hundred fourteen million, seven hundred forty-three thousand, seven hundred twenty".