20131977 has 4 divisors (see below), whose sum is σ = 26842640. Its totient is φ = 13421316.

The previous prime is 20131939. The next prime is 20131981. The reversal of 20131977 is 77913102.

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 20131977 - 2¹¹ = 20129929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20131907) 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, 3355327 + ... + 3355332.

It is an arithmetic number, because the mean of its divisors is an integer number (6710660).

Almost surely, 2^20131977 is an apocalyptic number.

It is an amenable number.

20131977 is a deficient number, since it is larger than the sum of its proper divisors (6710663).

20131977 is an equidigital number, since it uses as much as digits as its factorization.

20131977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6710662.

The product of its (nonzero) digits is 2646, while the sum is 30.

The square root of 20131977 is about 4486.8671698636. The cubic root of 20131977 is about 272.0375209557.

The spelling of 20131977 in words is "twenty million, one hundred thirty-one thousand, nine hundred seventy-seven".