20988377 has 2 divisors, whose sum is σ = 20988378. Its totient is φ = 20988376.

The previous prime is 20988349. The next prime is 20988391. The reversal of 20988377 is 77388902.

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., 15531481 + 5456896 = 3941^2 + 2336^2 .

It is a cyclic number.

It is not a de Polignac number, because 20988377 - 2⁶ = 20988313 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20988307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10494188 + 10494189.

It is an arithmetic number, because the mean of its divisors is an integer number (10494189).

Almost surely, 2^20988377 is an apocalyptic number.

It is an amenable number.

20988377 is a deficient number, since it is larger than the sum of its proper divisors (1).

20988377 is an equidigital number, since it uses as much as digits as its factorization.

20988377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 20988377 is about 4581.3073461622. The cubic root of 20988377 is about 275.8415082832.

The spelling of 20988377 in words is "twenty million, nine hundred eighty-eight thousand, three hundred seventy-seven".