7919042121 has 9 divisors (see below), whose sum is σ = 11439002029. Its totient is φ = 5279183436.

The previous prime is 7919042111. The next prime is 7919042171. The reversal of 7919042121 is 1212409197.

The square root of 7919042121 is 88989.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 7919042121 - 2⁷ = 7919041993 is a prime.

It is a super-2 number, since 2×7919042121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7919042111) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 252136 + ... + 281798.

Almost surely, 2^7919042121 is an apocalyptic number.

7919042121 is the 88989-th square number.

7919042121 is the 44495-th centered octagonal number.

It is an amenable number.

7919042121 is a deficient number, since it is larger than the sum of its proper divisors (3519959908).

7919042121 is an frugal number, since it uses more digits than its factorization.

7919042121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59332 (or 29666 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The cubic root of 7919042121 is about 1993.2306237059.

Multiplying 7919042121 by its sum of digits (36), we get a square (285085516356 = 533934²).

The spelling of 7919042121 in words is "seven billion, nine hundred nineteen million, forty-two thousand, one hundred twenty-one".