261464643 has 48 divisors (see below), whose sum is σ = 436300800. Its totient is φ = 149221440.

The previous prime is 261464587. The next prime is 261464653. The reversal of 261464643 is 346464162.

261464643 is a `hidden beast` number, since 2 + 6 + 1 + 4 + 6 + 4 + 643 = 666.

261464643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261464643 - 2⁶ = 261464579 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261464598 and 261464607.

It is not an unprimeable number, because it can be changed into a prime (261464653) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 430446 + ... + 431052.

It is an arithmetic number, because the mean of its divisors is an integer number (9089600).

Almost surely, 2^261464643 is an apocalyptic number.

261464643 is a deficient number, since it is larger than the sum of its proper divisors (174836157).

261464643 is a wasteful number, since it uses less digits than its factorization.

261464643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 872 (or 869 counting only the distinct ones).

The product of its digits is 82944, while the sum is 36.

The square root of 261464643 is about 16169.8683668112. The cubic root of 261464643 is about 639.4466595809.

It can be divided in two parts, 2614646 and 43, that added together give a square (2614689 = 1617²).

The spelling of 261464643 in words is "two hundred sixty-one million, four hundred sixty-four thousand, six hundred forty-three".