261665452464 has 80 divisors (see below), whose sum is σ = 728037902592. Its totient is φ = 80504573184.

The previous prime is 261665452453. The next prime is 261665452547. The reversal of 261665452464 is 464254566162.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12124147 + ... + 12145709.

Almost surely, 2^261665452464 is an apocalyptic number.

261665452464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

261665452464 is an abundant number, since it is smaller than the sum of its proper divisors (466372450128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261665452464 is a wasteful number, since it uses less digits than its factorization.

261665452464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41034 (or 41028 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 51.

The spelling of 261665452464 in words is "two hundred sixty-one billion, six hundred sixty-five million, four hundred fifty-two thousand, four hundred sixty-four".