20545977 has 4 divisors (see below), whose sum is σ = 27394640. Its totient is φ = 13697316.

The previous prime is 20545957. The next prime is 20546023. The reversal of 20545977 is 77954502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20545977 - 2¹² = 20541881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20545907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3424327 + ... + 3424332.

It is an arithmetic number, because the mean of its divisors is an integer number (6848660).

Almost surely, 2^20545977 is an apocalyptic number.

It is an amenable number.

20545977 is a deficient number, since it is larger than the sum of its proper divisors (6848663).

20545977 is an equidigital number, since it uses as much as digits as its factorization.

20545977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6848662.

The product of its (nonzero) digits is 88200, while the sum is 39.

The square root of 20545977 is about 4532.7670357079. The cubic root of 20545977 is about 273.8896362320.

The spelling of 20545977 in words is "twenty million, five hundred forty-five thousand, nine hundred seventy-seven".