1601551643640 has 64 divisors (see below), whose sum is σ = 5174243776800. Its totient is φ = 394228096512.

The previous prime is 1601551643617. The next prime is 1601551643647. The reversal of 1601551643640 is 463461551061.

It is a junction number, because it is equal to n+sod(n) for n = 1601551643592 and 1601551643601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601551643647) 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, 513316275 + ... + 513319394.

Almost surely, 2^{1601551643640} is an apocalyptic number.

1601551643640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1601551643640 is an abundant number, since it is smaller than the sum of its proper divisors (3572692133160).

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

1601551643640 is a wasteful number, since it uses less digits than its factorization.

1601551643640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026635696 (or 1026635692 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 42.

The spelling of 1601551643640 in words is "one trillion, six hundred one billion, five hundred fifty-one million, six hundred forty-three thousand, six hundred forty".