261262653740 has 96 divisors (see below), whose sum is σ = 624207403008. Its totient is φ = 90991872000.

The previous prime is 261262653733. The next prime is 261262653797. The reversal of 261262653740 is 47356262162.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 261262653691 and 261262653700.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 464075 + ... + 859005.

It is an arithmetic number, because the mean of its divisors is an integer number (6502160448).

Almost surely, 2^261262653740 is an apocalyptic number.

261262653740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261262653740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312103701504).

261262653740 is an abundant number, since it is smaller than the sum of its proper divisors (362944749268).

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

261262653740 is a wasteful number, since it uses less digits than its factorization.

261262653740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395079 (or 395077 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 44.

The spelling of 261262653740 in words is "two hundred sixty-one billion, two hundred sixty-two million, six hundred fifty-three thousand, seven hundred forty".