1661276712810 has 192 divisors, whose sum is σ = 4882337389440. Its totient is φ = 358934822400.

The previous prime is 1661276712803. The next prime is 1661276712817. The reversal of 1661276712810 is 182176721661.

It is an interprime number because it is at equal distance from previous prime (1661276712803) and next prime (1661276712817).

It is a super-2 number, since 2×1661276712810² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1661276712810.

It is not an unprimeable number, because it can be changed into a prime (1661276712817) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 761545 + ... + 1975475.

It is an arithmetic number, because the mean of its divisors is an integer number (25428840570).

Almost surely, 2^{1661276712810} is an apocalyptic number.

1661276712810 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661276712810, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2441168694720).

1661276712810 is an abundant number, since it is smaller than the sum of its proper divisors (3221060676630).

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

1661276712810 is a wasteful number, since it uses less digits than its factorization.

1661276712810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1214005 (or 1213994 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 48.

The spelling of 1661276712810 in words is "one trillion, six hundred sixty-one billion, two hundred seventy-six million, seven hundred twelve thousand, eight hundred ten".