1815955201 has 2 divisors, whose sum is σ = 1815955202. Its totient is φ = 1815955200.

The previous prime is 1815955129. The next prime is 1815955213. The reversal of 1815955201 is 1025595181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1646330625 + 169624576 = 40575^2 + 13024^2 .

It is a cyclic number.

It is not a de Polignac number, because 1815955201 - 2⁷ = 1815955073 is a prime.

It is not a weakly prime, because it can be changed into another prime (1815955241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 907977600 + 907977601.

It is an arithmetic number, because the mean of its divisors is an integer number (907977601).

Almost surely, 2^1815955201 is an apocalyptic number.

It is an amenable number.

1815955201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1815955201 is an equidigital number, since it uses as much as digits as its factorization.

1815955201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18000, while the sum is 37.

The square root of 1815955201 is about 42614.0258717714. The cubic root of 1815955201 is about 1220.0240076347.

The spelling of 1815955201 in words is "one billion, eight hundred fifteen million, nine hundred fifty-five thousand, two hundred one".