261672651 has 6 divisors (see below), whose sum is σ = 377971620. Its totient is φ = 174448428.

The previous prime is 261672647. The next prime is 261672659. The reversal of 261672651 is 156276162.

It is a happy number.

It is not a de Polignac number, because 261672651 - 2² = 261672647 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261672659) 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 5 ways as a sum of consecutive naturals, for example, 14537361 + ... + 14537378.

It is an arithmetic number, because the mean of its divisors is an integer number (62995270).

Almost surely, 2^261672651 is an apocalyptic number.

261672651 is a deficient number, since it is larger than the sum of its proper divisors (116298969).

261672651 is a wasteful number, since it uses less digits than its factorization.

261672651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29074745 (or 29074742 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 261672651 is about 16176.2990513900. The cubic root of 261672651 is about 639.6161850699.

The spelling of 261672651 in words is "two hundred sixty-one million, six hundred seventy-two thousand, six hundred fifty-one".