1218172401 has 12 divisors (see below), whose sum is σ = 1759884880. Its totient is φ = 811975320.

The previous prime is 1218172393. The next prime is 1218172411. The reversal of 1218172401 is 1042718121.

1218172401 is a `hidden beast` number, since 12 + 181 + 72 + 401 = 666.

It is not a de Polignac number, because 1218172401 - 2³ = 1218172393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1218172411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 97530 + ... + 109308.

Almost surely, 2^1218172401 is an apocalyptic number.

It is an amenable number.

1218172401 is a deficient number, since it is larger than the sum of its proper divisors (541712479).

1218172401 is a wasteful number, since it uses less digits than its factorization.

1218172401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23276 (or 23273 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 27.

The square root of 1218172401 is about 34902.3265843411. The cubic root of 1218172401 is about 1067.9958995971.

The spelling of 1218172401 in words is "one billion, two hundred eighteen million, one hundred seventy-two thousand, four hundred one".