261421764671623 has 8 divisors (see below), whose sum is σ = 262271729943776. Its totient is φ = 260573178096000.

The previous prime is 261421764671597. The next prime is 261421764671647. The reversal of 261421764671623 is 326176467124162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261421764671623 - 2¹³ = 261421764663431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261421764671923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 344294286 + ... + 345052747.

It is an arithmetic number, because the mean of its divisors is an integer number (32783966242972).

Almost surely, 2^{261421764671623} is an apocalyptic number.

261421764671623 is a deficient number, since it is larger than the sum of its proper divisors (849965272153).

261421764671623 is an equidigital number, since it uses as much as digits as its factorization.

261421764671623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689348265.

The product of its digits is 24385536, while the sum is 58.

The spelling of 261421764671623 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, seven hundred sixty-four million, six hundred seventy-one thousand, six hundred twenty-three".