7121155 has 4 divisors (see below), whose sum is σ = 8545392. Its totient is φ = 5696920.

The previous prime is 7121141. The next prime is 7121161. The reversal of 7121155 is 5511217.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5511217 = 659 ⋅8363.

It is a de Polignac number, because none of the positive numbers 2^k-7121155 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 712111 + ... + 712120.

It is an arithmetic number, because the mean of its divisors is an integer number (2136348).

Almost surely, 2^7121155 is an apocalyptic number.

7121155 is a deficient number, since it is larger than the sum of its proper divisors (1424237).

7121155 is a wasteful number, since it uses less digits than its factorization.

7121155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1424236.

The product of its digits is 350, while the sum is 22.

The square root of 7121155 is about 2668.5492313240. The cubic root of 7121155 is about 192.3904363312.

The spelling of 7121155 in words is "seven million, one hundred twenty-one thousand, one hundred fifty-five".