261907166907 has 32 divisors (see below), whose sum is σ = 391649280000. Its totient is φ = 172969001856.

The previous prime is 261907166881. The next prime is 261907166947. The reversal of 261907166907 is 709661709162.

261907166907 is a `hidden beast` number, since 2 + 619 + 0 + 7 + 16 + 6 + 9 + 0 + 7 = 666.

It is not a de Polignac number, because 261907166907 - 2³¹ = 259759683259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261907166947) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6077478 + ... + 6120420.

It is an arithmetic number, because the mean of its divisors is an integer number (12239040000).

Almost surely, 2^261907166907 is an apocalyptic number.

261907166907 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

261907166907 is a deficient number, since it is larger than the sum of its proper divisors (129742113093).

261907166907 is a wasteful number, since it uses less digits than its factorization.

261907166907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45064 (or 45058 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 54.

The spelling of 261907166907 in words is "two hundred sixty-one billion, nine hundred seven million, one hundred sixty-six thousand, nine hundred seven".