1620818180261 has 16 divisors (see below), whose sum is σ = 1855875649536. Its totient is φ = 1386640224816.

The previous prime is 1620818180227. The next prime is 1620818180339.

1620818180261 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1620818180261 - 2⁶ = 1620818180197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620818189261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13195250 + ... + 13317516.

It is an arithmetic number, because the mean of its divisors is an integer number (115992228096).

Almost surely, 2^{1620818180261} is an apocalyptic number.

It is an amenable number.

1620818180261 is a deficient number, since it is larger than the sum of its proper divisors (235057469275).

1620818180261 is a wasteful number, since it uses less digits than its factorization.

1620818180261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125848.

The product of its (nonzero) digits is 73728, while the sum is 44.

The spelling of 1620818180261 in words is "one trillion, six hundred twenty billion, eight hundred eighteen million, one hundred eighty thousand, two hundred sixty-one".