1621433436540 has 48 divisors (see below), whose sum is σ = 4542956210688. Its totient is φ = 432102003264.

The previous prime is 1621433436529. The next prime is 1621433436589. The reversal of 1621433436540 is 456343341261.

It is a junction number, because it is equal to n+sod(n) for n = 1621433436492 and 1621433436501.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 8664352 + ... + 8849511.

It is an arithmetic number, because the mean of its divisors is an integer number (94644921056).

Almost surely, 2^{1621433436540} is an apocalyptic number.

1621433436540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1621433436540 is an abundant number, since it is smaller than the sum of its proper divisors (2921522774148).

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

1621433436540 is a wasteful number, since it uses less digits than its factorization.

1621433436540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17515418 (or 17515416 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 42.

The spelling of 1621433436540 in words is "one trillion, six hundred twenty-one billion, four hundred thirty-three million, four hundred thirty-six thousand, five hundred forty".