1921907449 has 24 divisors (see below), whose sum is σ = 2473333056. Its totient is φ = 1476468000.

The previous prime is 1921907447. The next prime is 1921907467. The reversal of 1921907449 is 9447091291.

It is not a de Polignac number, because 1921907449 - 2¹ = 1921907447 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1921907399 and 1921907408.

It is not an unprimeable number, because it can be changed into a prime (1921907447) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13159 + ... + 63379.

It is an arithmetic number, because the mean of its divisors is an integer number (103055544).

Almost surely, 2^1921907449 is an apocalyptic number.

It is an amenable number.

1921907449 is a deficient number, since it is larger than the sum of its proper divisors (551425607).

1921907449 is a wasteful number, since it uses less digits than its factorization.

1921907449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50317 (or 50310 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 46.

The square root of 1921907449 is about 43839.5648815086. The cubic root of 1921907449 is about 1243.3044555693.

The spelling of 1921907449 in words is "one billion, nine hundred twenty-one million, nine hundred seven thousand, four hundred forty-nine".