261533004 has 24 divisors (see below), whose sum is σ = 623228928. Its totient is φ = 85322640.

The previous prime is 261533003. The next prime is 261533029. The reversal of 261533004 is 400335162.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (261533003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 231292 + ... + 232419.

It is an arithmetic number, because the mean of its divisors is an integer number (25967872).

Almost surely, 2^261533004 is an apocalyptic number.

It is an amenable number.

261533004 is an abundant number, since it is smaller than the sum of its proper divisors (361695924).

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

261533004 is a wasteful number, since it uses less digits than its factorization.

261533004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463765 (or 463763 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 261533004 is about 16171.9820677615. The cubic root of 261533004 is about 639.5023833727.

Adding to 261533004 its reverse (400335162), we get a palindrome (661868166).

The spelling of 261533004 in words is "two hundred sixty-one million, five hundred thirty-three thousand, four".