261255442650 has 48 divisors (see below), whose sum is σ = 658895104800. Its totient is φ = 68487300160.

The previous prime is 261255442603. The next prime is 261255442661. The reversal of 261255442650 is 56244552162.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14751345 + ... + 14769044.

It is an arithmetic number, because the mean of its divisors is an integer number (13726981350).

Almost surely, 2^261255442650 is an apocalyptic number.

261255442650 is an abundant number, since it is smaller than the sum of its proper divisors (397639662150).

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

261255442650 is a wasteful number, since it uses less digits than its factorization.

261255442650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29520463 (or 29520458 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 42.

The spelling of 261255442650 in words is "two hundred sixty-one billion, two hundred fifty-five million, four hundred forty-two thousand, six hundred fifty".