261762540 has 96 divisors (see below), whose sum is σ = 823689216. Its totient is φ = 61628160.

The previous prime is 261762521. The next prime is 261762541. The reversal of 261762540 is 45267162.

It is not an unprimeable number, because it can be changed into a prime (261762541) 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 31 ways as a sum of consecutive naturals, for example, 10645 + ... + 25235.

It is an arithmetic number, because the mean of its divisors is an integer number (8580096).

Almost surely, 2^261762540 is an apocalyptic number.

261762540 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 261762540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (411844608).

261762540 is an abundant number, since it is smaller than the sum of its proper divisors (561926676).

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

261762540 is a wasteful number, since it uses less digits than its factorization.

261762540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14639 (or 14637 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 261762540 is about 16179.0772295579. The cubic root of 261762540 is about 639.6894163595.

The spelling of 261762540 in words is "two hundred sixty-one million, seven hundred sixty-two thousand, five hundred forty".