7961280121 has 8 divisors (see below), whose sum is σ = 8179701704. Its totient is φ = 7743029760.

The previous prime is 7961280077. The next prime is 7961280127. The reversal of 7961280121 is 1210821697.

It can be written as a sum of positive squares in 4 ways, for example, as 2401490025 + 5559790096 = 49005^2 + 74564^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7961280121 - 2⁷ = 7961279993 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7961280127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54451 + ... + 137431.

It is an arithmetic number, because the mean of its divisors is an integer number (1022462713).

Almost surely, 2^7961280121 is an apocalyptic number.

It is an amenable number.

7961280121 is a deficient number, since it is larger than the sum of its proper divisors (218421583).

7961280121 is a wasteful number, since it uses less digits than its factorization.

7961280121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85611.

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 7961280121 is about 89226.0058559162. The cubic root of 7961280121 is about 1996.7681237176.

The spelling of 7961280121 in words is "seven billion, nine hundred sixty-one million, two hundred eighty thousand, one hundred twenty-one".