261166454456370 has 128 divisors (see below), whose sum is σ = 639912354916608. Its totient is φ = 68198017305600.

The previous prime is 261166454456293. The next prime is 261166454456429. The reversal of 261166454456370 is 73654454661162.

It is a super-2 number, since 2×261166454456370² (a number of 30 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 565823080 + ... + 566284460.

It is an arithmetic number, because the mean of its divisors is an integer number (4999315272786).

Almost surely, 2^{261166454456370} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261166454456370, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319956177458304).

261166454456370 is an abundant number, since it is smaller than the sum of its proper divisors (378745900460238).

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

261166454456370 is a wasteful number, since it uses less digits than its factorization.

261166454456370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462828.

The product of its (nonzero) digits is 87091200, while the sum is 60.

The spelling of 261166454456370 in words is "two hundred sixty-one trillion, one hundred sixty-six billion, four hundred fifty-four million, four hundred fifty-six thousand, three hundred seventy".