7121913 has 4 divisors (see below), whose sum is σ = 9495888. Its totient is φ = 4747940.

The previous prime is 7121879. The next prime is 7121921. The reversal of 7121913 is 3191217.

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, and also an emirpimes, since its reverse is a distinct semiprime: 3191217 = 3 ⋅1063739.

It is a cyclic number.

It is not a de Polignac number, because 7121913 - 2¹³ = 7113721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7121923) 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, 1186983 + ... + 1186988.

It is an arithmetic number, because the mean of its divisors is an integer number (2373972).

Almost surely, 2^7121913 is an apocalyptic number.

It is an amenable number.

7121913 is a deficient number, since it is larger than the sum of its proper divisors (2373975).

7121913 is a wasteful number, since it uses less digits than its factorization.

7121913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2373974.

The product of its digits is 378, while the sum is 24.

The square root of 7121913 is about 2668.6912522808. The cubic root of 7121913 is about 192.3972623202.

The spelling of 7121913 in words is "seven million, one hundred twenty-one thousand, nine hundred thirteen".