261821376 has 56 divisors (see below), whose sum is σ = 769711440. Its totient is φ = 87273216.

The previous prime is 261821353. The next prime is 261821389. The reversal of 261821376 is 673128162.

261821376 is a `hidden beast` number, since 2 + 618 + 2 + 1 + 37 + 6 = 666.

261821376 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 261821376.

It is a congruent number.

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, 74031 + ... + 77486.

Almost surely, 2^261821376 is an apocalyptic number.

It is an amenable number.

261821376 is an abundant number, since it is smaller than the sum of its proper divisors (507890064).

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

261821376 is a wasteful number, since it uses less digits than its factorization.

261821376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151538 (or 151522 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 261821376 is about 16180.8954016766. The cubic root of 261821376 is about 639.7373401342.

The spelling of 261821376 in words is "two hundred sixty-one million, eight hundred twenty-one thousand, three hundred seventy-six".