20878541 has 2 divisors, whose sum is σ = 20878542. Its totient is φ = 20878540.

The previous prime is 20878537. The next prime is 20878577. The reversal of 20878541 is 14587802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14092516 + 6786025 = 3754^2 + 2605^2 .

It is a cyclic number.

It is not a de Polignac number, because 20878541 - 2² = 20878537 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20878591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10439270 + 10439271.

It is an arithmetic number, because the mean of its divisors is an integer number (10439271).

Almost surely, 2^20878541 is an apocalyptic number.

It is an amenable number.

20878541 is a deficient number, since it is larger than the sum of its proper divisors (1).

20878541 is an equidigital number, since it uses as much as digits as its factorization.

20878541 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 20878541 is about 4569.3042139914. The cubic root of 20878541 is about 275.3594901869.

The spelling of 20878541 in words is "twenty million, eight hundred seventy-eight thousand, five hundred forty-one".