261851500443 has 8 divisors (see below), whose sum is σ = 375991898128. Its totient is φ = 161139384864.

The previous prime is 261851500441. The next prime is 261851500451. The reversal of 261851500443 is 344005158162.

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

It is not a de Polignac number, because 261851500443 - 2¹ = 261851500441 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 6714141037 = 261851500443 / (2 + 6 + 1 + 8 + 5 + 1 + 5 + 0 + 0 + 4 + 4 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261851500441) 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, 3357070480 + ... + 3357070557.

It is an arithmetic number, because the mean of its divisors is an integer number (46998987266).

Almost surely, 2^261851500443 is an apocalyptic number.

261851500443 is a deficient number, since it is larger than the sum of its proper divisors (114140397685).

261851500443 is a wasteful number, since it uses less digits than its factorization.

261851500443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6714141053.

The product of its (nonzero) digits is 115200, while the sum is 39.

The spelling of 261851500443 in words is "two hundred sixty-one billion, eight hundred fifty-one million, five hundred thousand, four hundred forty-three".