261335533164 has 24 divisors (see below), whose sum is σ = 609791390208. Its totient is φ = 87110633040.

The previous prime is 261335533141. The next prime is 261335533183. The reversal of 261335533164 is 461335533162.

It is a super-2 number, since 2×261335533164² (a number of 24 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, 1317469 + ... + 1502795.

It is an arithmetic number, because the mean of its divisors is an integer number (25407974592).

Almost surely, 2^261335533164 is an apocalyptic number.

It is an amenable number.

261335533164 is an abundant number, since it is smaller than the sum of its proper divisors (348455857044).

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

261335533164 is a wasteful number, since it uses less digits than its factorization.

261335533164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302845 (or 302843 counting only the distinct ones).

The product of its digits is 583200, while the sum is 42.

The spelling of 261335533164 in words is "two hundred sixty-one billion, three hundred thirty-five million, five hundred thirty-three thousand, one hundred sixty-four".