20189381477 has 2 divisors, whose sum is σ = 20189381478. Its totient is φ = 20189381476.

The previous prime is 20189381453. The next prime is 20189381491. The reversal of 20189381477 is 77418398102.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20179338916 + 10042561 = 142054^2 + 3169^2 .

It is a cyclic number.

It is not a de Polignac number, because 20189381477 - 2⁶ = 20189381413 is a prime.

It is a super-2 number, since 2×20189381477² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20189381497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10094690738 + 10094690739.

It is an arithmetic number, because the mean of its divisors is an integer number (10094690739).

Almost surely, 2^20189381477 is an apocalyptic number.

It is an amenable number.

20189381477 is a deficient number, since it is larger than the sum of its proper divisors (1).

20189381477 is an equidigital number, since it uses as much as digits as its factorization.

20189381477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 677376, while the sum is 50.

The spelling of 20189381477 in words is "twenty billion, one hundred eighty-nine million, three hundred eighty-one thousand, four hundred seventy-seven".