188661262720021 has 192 divisors, whose sum is σ = 266522664038400. Its totient is φ = 131754813249024.

The previous prime is 188661262719991. The next prime is 188661262720031. The reversal of 188661262720021 is 120027262166881.

It is not a de Polignac number, because 188661262720021 - 2⁹ = 188661262719509 is a prime.

It is a super-2 number, since 2×188661262720021² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (188661262720031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1252597300 + ... + 1252747906.

It is an arithmetic number, because the mean of its divisors is an integer number (1388138875200).

Almost surely, 2^{188661262720021} is an apocalyptic number.

It is an amenable number.

188661262720021 is a deficient number, since it is larger than the sum of its proper divisors (77861401318379).

188661262720021 is a wasteful number, since it uses less digits than its factorization.

188661262720021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150808 (or 150801 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 52.

The spelling of 188661262720021 in words is "one hundred eighty-eight trillion, six hundred sixty-one billion, two hundred sixty-two million, seven hundred twenty thousand, twenty-one".