8619513921 has 6 divisors (see below), whose sum is σ = 12450409010. Its totient is φ = 5746342608.

The previous prime is 8619513901. The next prime is 8619513937. The reversal of 8619513921 is 1293159168.

8619513921 is a `hidden beast` number, since 8 + 619 + 5 + 1 + 3 + 9 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 8582169600 + 37344321 = 92640^2 + 6111^2 .

It is not a de Polignac number, because 8619513921 - 2⁶ = 8619513857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (8619513901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 478861876 + ... + 478861893.

Almost surely, 2^8619513921 is an apocalyptic number.

It is an amenable number.

8619513921 is a deficient number, since it is larger than the sum of its proper divisors (3830895089).

8619513921 is a wasteful number, since it uses less digits than its factorization.

8619513921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 957723775 (or 957723772 counting only the distinct ones).

The product of its digits is 116640, while the sum is 45.

The square root of 8619513921 is about 92841.3373503420. The cubic root of 8619513921 is about 2050.3480607502.

The spelling of 8619513921 in words is "eight billion, six hundred nineteen million, five hundred thirteen thousand, nine hundred twenty-one".