20157889 has 2 divisors, whose sum is σ = 20157890. Its totient is φ = 20157888.

The previous prime is 20157833. The next prime is 20157911. The reversal of 20157889 is 98875102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18447025 + 1710864 = 4295^2 + 1308^2 .

It is a cyclic number.

It is not a de Polignac number, because 20157889 - 2¹³ = 20149697 is a prime.

It is not a weakly prime, because it can be changed into another prime (20157589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10078944 + 10078945.

It is an arithmetic number, because the mean of its divisors is an integer number (10078945).

Almost surely, 2^20157889 is an apocalyptic number.

It is an amenable number.

20157889 is a deficient number, since it is larger than the sum of its proper divisors (1).

20157889 is an equidigital number, since it uses as much as digits as its factorization.

20157889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 20157889 is about 4489.7537794405. The cubic root of 20157889 is about 272.1541846779.

The spelling of 20157889 in words is "twenty million, one hundred fifty-seven thousand, eight hundred eighty-nine".