261371630 has 32 divisors (see below), whose sum is σ = 518452704. Its totient is φ = 94260096.

The previous prime is 261371611. The next prime is 261371639. The reversal of 261371630 is 36173162.

It is a junction number, because it is equal to n+sod(n) for n = 261371593 and 261371602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261371639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17789 + ... + 28968.

It is an arithmetic number, because the mean of its divisors is an integer number (16201647).

Almost surely, 2^261371630 is an apocalyptic number.

261371630 is a deficient number, since it is larger than the sum of its proper divisors (257081074).

261371630 is a wasteful number, since it uses less digits than its factorization.

261371630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46820.

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 261371630 is about 16166.9919898539. The cubic root of 261371630 is about 639.3708253552.

The spelling of 261371630 in words is "two hundred sixty-one million, three hundred seventy-one thousand, six hundred thirty".