7777121 has 4 divisors (see below), whose sum is σ = 8484144. Its totient is φ = 7070100.

The previous prime is 7777103. The next prime is 7777139. The reversal of 7777121 is 1217777.

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 an interprime number because it is at equal distance from previous prime (7777103) and next prime (7777139).

It is a cyclic number.

It is not a de Polignac number, because 7777121 - 2¹⁸ = 7514977 is a prime.

It is a super-2 number, since 2×7777121² = 120967222097282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7777171) 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 3 ways as a sum of consecutive naturals, for example, 353495 + ... + 353516.

It is an arithmetic number, because the mean of its divisors is an integer number (2121036).

Almost surely, 2^7777121 is an apocalyptic number.

It is an amenable number.

7777121 is a deficient number, since it is larger than the sum of its proper divisors (707023).

7777121 is a wasteful number, since it uses less digits than its factorization.

7777121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707022.

The product of its digits is 4802, while the sum is 32.

The square root of 7777121 is about 2788.7490026892. The cubic root of 7777121 is about 198.1251546934.

The spelling of 7777121 in words is "seven million, seven hundred seventy-seven thousand, one hundred twenty-one".