261669828 has 24 divisors (see below), whose sum is σ = 697786432. Its totient is φ = 74762784.

The previous prime is 261669823. The next prime is 261669829. The reversal of 261669828 is 828966162.

It is a happy number.

261669828 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (261669823) 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, 1557475 + ... + 1557642.

Almost surely, 2^261669828 is an apocalyptic number.

261669828 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

261669828 is an abundant number, since it is smaller than the sum of its proper divisors (436116604).

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

261669828 is a wasteful number, since it uses less digits than its factorization.

261669828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3115131 (or 3115129 counting only the distinct ones).

The product of its digits is 497664, while the sum is 48.

The square root of 261669828 is about 16176.2117938657. The cubic root of 261669828 is about 639.6138849403.

The spelling of 261669828 in words is "two hundred sixty-one million, six hundred sixty-nine thousand, eight hundred twenty-eight".