1611273121640 has 64 divisors (see below), whose sum is σ = 4461987116160. Its totient is φ = 509941382400.

The previous prime is 1611273121583. The next prime is 1611273121649. The reversal of 1611273121640 is 461213721161.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 1611273121640.

It is not an unprimeable number, because it can be changed into a prime (1611273121649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 221325086 + ... + 221332365.

It is an arithmetic number, because the mean of its divisors is an integer number (69718548690).

Almost surely, 2^{1611273121640} is an apocalyptic number.

1611273121640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1611273121640 is an abundant number, since it is smaller than the sum of its proper divisors (2850713994520).

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

1611273121640 is a wasteful number, since it uses less digits than its factorization.

1611273121640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442657482 (or 442657478 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 35.

The spelling of 1611273121640 in words is "one trillion, six hundred eleven billion, two hundred seventy-three million, one hundred twenty-one thousand, six hundred forty".