19877949 has 36 divisors (see below), whose sum is σ = 35551776. Its totient is φ = 10479456.

The previous prime is 19877909. The next prime is 19877951. The reversal of 19877949 is 94977891.

It is not a de Polignac number, because 19877949 - 2¹² = 19873853 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 19877895 and 19877904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19877909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 9714 + ... + 11580.

Almost surely, 2^19877949 is an apocalyptic number.

It is an amenable number.

19877949 is a deficient number, since it is larger than the sum of its proper divisors (15673827).

19877949 is a wasteful number, since it uses less digits than its factorization.

19877949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1906 (or 1890 counting only the distinct ones).

The product of its digits is 1143072, while the sum is 54.

The square root of 19877949 is about 4458.4693561804. The cubic root of 19877949 is about 270.8884723290. Note that the first 3 decimals are identical.

The spelling of 19877949 in words is "nineteen million, eight hundred seventy-seven thousand, nine hundred forty-nine".