1611621461645 has 16 divisors (see below), whose sum is σ = 2082737400240. Its totient is φ = 1190105270784.

The previous prime is 1611621461627. The next prime is 1611621461699. The reversal of 1611621461645 is 5461641261161.

It can be written as a sum of positive squares in 8 ways, for example, as 203893790116 + 1407727671529 = 451546^2 + 1186477^2 .

It is a cyclic number.

It is not a de Polignac number, because 1611621461645 - 2¹² = 1611621457549 is a prime.

It is a super-3 number, since 3×1611621461645³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 1611621461596 and 1611621461605.

It is a congruent number.

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, 9166121 + ... + 9340289.

It is an arithmetic number, because the mean of its divisors is an integer number (130171087515).

Almost surely, 2^{1611621461645} is an apocalyptic number.

It is an amenable number.

1611621461645 is a deficient number, since it is larger than the sum of its proper divisors (471115938595).

1611621461645 is a wasteful number, since it uses less digits than its factorization.

1611621461645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316544.

The product of its digits is 207360, while the sum is 44.

The spelling of 1611621461645 in words is "one trillion, six hundred eleven billion, six hundred twenty-one million, four hundred sixty-one thousand, six hundred forty-five".