201556361663 has 4 divisors (see below), whose sum is σ = 201569690520. Its totient is φ = 201543032808.

The previous prime is 201556361647. The next prime is 201556361681. The reversal of 201556361663 is 366163655102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201556361663 - 2⁴ = 201556361647 is a prime.

It is a super-2 number, since 2×201556361663² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201556361263) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6641720 + ... + 6671997.

It is an arithmetic number, because the mean of its divisors is an integer number (50392422630).

Almost surely, 2^201556361663 is an apocalyptic number.

201556361663 is a deficient number, since it is larger than the sum of its proper divisors (13328857).

201556361663 is a wasteful number, since it uses less digits than its factorization.

201556361663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13328856.

The product of its (nonzero) digits is 583200, while the sum is 44.

The spelling of 201556361663 in words is "two hundred one billion, five hundred fifty-six million, three hundred sixty-one thousand, six hundred sixty-three".