2181620663001 has 12 divisors (see below), whose sum is σ = 3393632142628. Its totient is φ = 1342535792544.

The previous prime is 2181620662997. The next prime is 2181620663071. The reversal of 2181620663001 is 1003660261812.

It is a happy number.

2181620663001 is a `hidden beast` number, since 2 + 1 + 8 + 16 + 2 + 0 + 6 + 630 + 0 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 89446453776 + 2092174209225 = 299076^2 + 1446435^2 .

It is not a de Polignac number, because 2181620663001 - 2² = 2181620662997 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2181620663071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9323165110 + ... + 9323165343.

Almost surely, 2^{2181620663001} is an apocalyptic number.

It is an amenable number.

2181620663001 is a deficient number, since it is larger than the sum of its proper divisors (1212011479627).

2181620663001 is a wasteful number, since it uses less digits than its factorization.

2181620663001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18646330472 (or 18646330469 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 2181620663001 in words is "two trillion, one hundred eighty-one billion, six hundred twenty million, six hundred sixty-three thousand, one".