21888356377 has 2 divisors, whose sum is σ = 21888356378. Its totient is φ = 21888356376.

The previous prime is 21888356333. The next prime is 21888356407. The reversal of 21888356377 is 77365388812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18600595456 + 3287760921 = 136384^2 + 57339^2 .

It is a cyclic number.

It is not a de Polignac number, because 21888356377 - 2¹⁵ = 21888323609 is a prime.

It is a super-2 number, since 2×21888356377² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21828356377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10944178188 + 10944178189.

It is an arithmetic number, because the mean of its divisors is an integer number (10944178189).

Almost surely, 2^21888356377 is an apocalyptic number.

It is an amenable number.

21888356377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21888356377 is an equidigital number, since it uses as much as digits as its factorization.

21888356377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13547520, while the sum is 58.

The spelling of 21888356377 in words is "twenty-one billion, eight hundred eighty-eight million, three hundred fifty-six thousand, three hundred seventy-seven".