1621801952611 has 8 divisors (see below), whose sum is σ = 1630647474624. Its totient is φ = 1612975353000.

The previous prime is 1621801952543. The next prime is 1621801952621. The reversal of 1621801952611 is 1162591081261.

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

It is a cyclic number.

It is not a de Polignac number, because 1621801952611 - 2²³ = 1621793564003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1621801952621) 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, 4558701 + ... + 4901566.

It is an arithmetic number, because the mean of its divisors is an integer number (203830934328).

Almost surely, 2^{1621801952611} is an apocalyptic number.

1621801952611 is a deficient number, since it is larger than the sum of its proper divisors (8845522013).

1621801952611 is an equidigital number, since it uses as much as digits as its factorization.

1621801952611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9461201.

The product of its (nonzero) digits is 51840, while the sum is 43.

The spelling of 1621801952611 in words is "one trillion, six hundred twenty-one billion, eight hundred one million, nine hundred fifty-two thousand, six hundred eleven".