1621662153603 has 8 divisors (see below), whose sum is σ = 2236775384400. Its totient is φ = 1043828512608.

The previous prime is 1621662153593. The next prime is 1621662153637. The reversal of 1621662153603 is 3063512661261.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1621662153603 - 2⁹ = 1621662153091 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621662153203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9319897348 + ... + 9319897521.

It is an arithmetic number, because the mean of its divisors is an integer number (279596923050).

Almost surely, 2^{1621662153603} is an apocalyptic number.

1621662153603 is a deficient number, since it is larger than the sum of its proper divisors (615113230797).

1621662153603 is a wasteful number, since it uses less digits than its factorization.

1621662153603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18639794901.

The product of its (nonzero) digits is 233280, while the sum is 42.

The spelling of 1621662153603 in words is "one trillion, six hundred twenty-one billion, six hundred sixty-two million, one hundred fifty-three thousand, six hundred three".