261786546 has 64 divisors (see below), whose sum is σ = 671535360. Its totient is φ = 74044800.

The previous prime is 261786479. The next prime is 261786559. The reversal of 261786546 is 645687162.

261786546 is a `hidden beast` number, since 26 + 1 + 7 + 86 + 546 = 666.

It is a super-2 number, since 2×261786546² = 137064391333220232, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34750 + ... + 41606.

It is an arithmetic number, because the mean of its divisors is an integer number (10492740).

Almost surely, 2^261786546 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261786546, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (335767680).

261786546 is an abundant number, since it is smaller than the sum of its proper divisors (409748814).

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

261786546 is a wasteful number, since it uses less digits than its factorization.

261786546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6976 (or 6970 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The square root of 261786546 is about 16179.8190966401. The cubic root of 261786546 is about 639.7089708696.

The spelling of 261786546 in words is "two hundred sixty-one million, seven hundred eighty-six thousand, five hundred forty-six".