1620730617645 has 96 divisors (see below), whose sum is σ = 2764159689600. Its totient is φ = 808668168192.

The previous prime is 1620730617641. The next prime is 1620730617697. The reversal of 1620730617645 is 5467160370261.

It is a happy number.

It is not a de Polignac number, because 1620730617645 - 2² = 1620730617641 is a prime.

It is a super-3 number, since 3×1620730617645³ (a number of 38 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1620730617594 and 1620730617603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620730617641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1744596541 + ... + 1744597469.

It is an arithmetic number, because the mean of its divisors is an integer number (28793330100).

Almost surely, 2^{1620730617645} is an apocalyptic number.

1620730617645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1620730617645 is a deficient number, since it is larger than the sum of its proper divisors (1143429071955).

1620730617645 is a wasteful number, since it uses less digits than its factorization.

1620730617645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1739 (or 1636 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 48.

The spelling of 1620730617645 in words is "one trillion, six hundred twenty billion, seven hundred thirty million, six hundred seventeen thousand, six hundred forty-five".