4978923121 has 2 divisors, whose sum is σ = 4978923122. Its totient is φ = 4978923120.

The previous prime is 4978923119. The next prime is 4978923133. The reversal of 4978923121 is 1213298794.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4397148721 + 581774400 = 66311^2 + 24120^2 .

It is a cyclic number.

It is not a de Polignac number, because 4978923121 - 2¹ = 4978923119 is a prime.

Together with 4978923119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (4978923101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2489461560 + 2489461561.

It is an arithmetic number, because the mean of its divisors is an integer number (2489461561).

Almost surely, 2^4978923121 is an apocalyptic number.

It is an amenable number.

4978923121 is a deficient number, since it is larger than the sum of its proper divisors (1).

4978923121 is an equidigital number, since it uses as much as digits as its factorization.

4978923121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 46.

The square root of 4978923121 is about 70561.4846853437. The cubic root of 4978923121 is about 1707.5698322026.

The spelling of 4978923121 in words is "four billion, nine hundred seventy-eight million, nine hundred twenty-three thousand, one hundred twenty-one".