2021188645757 has 2 divisors, whose sum is σ = 2021188645758. Its totient is φ = 2021188645756.

The previous prime is 2021188645747. The next prime is 2021188645873. The reversal of 2021188645757 is 7575468811202.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1921622523076 + 99566122681 = 1386226^2 + 315541^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021188645757 - 2⁸ = 2021188645501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021188645717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010594322878 + 1010594322879.

It is an arithmetic number, because the mean of its divisors is an integer number (1010594322879).

Almost surely, 2^{2021188645757} is an apocalyptic number.

It is an amenable number.

2021188645757 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021188645757 is an equidigital number, since it uses as much as digits as its factorization.

2021188645757 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7526400, while the sum is 56.

The spelling of 2021188645757 in words is "two trillion, twenty-one billion, one hundred eighty-eight million, six hundred forty-five thousand, seven hundred fifty-seven".