154221979 has 2 divisors, whose sum is σ = 154221980. Its totient is φ = 154221978.

The previous prime is 154221973. The next prime is 154222049. The reversal of 154221979 is 979122451.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-154221979 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (154221973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77110989 + 77110990.

It is an arithmetic number, because the mean of its divisors is an integer number (77110990).

Almost surely, 2^154221979 is an apocalyptic number.

154221979 is a deficient number, since it is larger than the sum of its proper divisors (1).

154221979 is an equidigital number, since it uses as much as digits as its factorization.

154221979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 154221979 is about 12418.6142141545. The cubic root of 154221979 is about 536.2682567414.

The spelling of 154221979 in words is "one hundred fifty-four million, two hundred twenty-one thousand, nine hundred seventy-nine".