100978321 has 2 divisors, whose sum is σ = 100978322. Its totient is φ = 100978320.

The previous prime is 100978309. The next prime is 100978373. The reversal of 100978321 is 123879001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97121025 + 3857296 = 9855^2 + 1964^2 .

It is a cyclic number.

It is not a de Polignac number, because 100978321 - 2⁵ = 100978289 is a prime.

It is not a weakly prime, because it can be changed into another prime (100978301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50489160 + 50489161.

It is an arithmetic number, because the mean of its divisors is an integer number (50489161).

Almost surely, 2^100978321 is an apocalyptic number.

It is an amenable number.

100978321 is a deficient number, since it is larger than the sum of its proper divisors (1).

100978321 is an equidigital number, since it uses as much as digits as its factorization.

100978321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 100978321 is about 10048.7969926753. The cubic root of 100978321 is about 465.6676284921.

The spelling of 100978321 in words is "one hundred million, nine hundred seventy-eight thousand, three hundred twenty-one".