7542636121 has 4 divisors (see below), whose sum is σ = 7580923812. Its totient is φ = 7504348432.

The previous prime is 7542636107. The next prime is 7542636191. The reversal of 7542636121 is 1216362457.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4894401600 + 2648234521 = 69960^2 + 51461^2 .

It is a cyclic number.

It is not a de Polignac number, because 7542636121 - 2⁵ = 7542636089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7542636191) 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, 19143550 + ... + 19143943.

It is an arithmetic number, because the mean of its divisors is an integer number (1895230953).

Almost surely, 2^7542636121 is an apocalyptic number.

It is an amenable number.

7542636121 is a deficient number, since it is larger than the sum of its proper divisors (38287691).

7542636121 is a wasteful number, since it uses less digits than its factorization.

7542636121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38287690.

The product of its digits is 60480, while the sum is 37.

The square root of 7542636121 is about 86848.3512854447. The cubic root of 7542636121 is about 1961.1360310810.

Adding to 7542636121 its reverse (1216362457), we get a palindrome (8758998578).

It can be divided in two parts, 754263 and 6121, that added together give a square (760384 = 872²).

The spelling of 7542636121 in words is "seven billion, five hundred forty-two million, six hundred thirty-six thousand, one hundred twenty-one".