261543210 has 32 divisors (see below), whose sum is σ = 637077312. Its totient is φ = 68703360.

The previous prime is 261543179. The next prime is 261543221. The reversal of 261543210 is 12345162.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63051 + ... + 67070.

It is an arithmetic number, because the mean of its divisors is an integer number (19908666).

Almost surely, 2^261543210 is an apocalyptic number.

261543210 is an abundant number, since it is smaller than the sum of its proper divisors (375534102).

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

261543210 is a wasteful number, since it uses less digits than its factorization.

261543210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130198.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 261543210 is about 16172.2976104201. The cubic root of 261543210 is about 639.5107018594.

Adding to 261543210 its reverse (12345162), we get a palindrome (273888372).

The spelling of 261543210 in words is "two hundred sixty-one million, five hundred forty-three thousand, two hundred ten".