1801201951 has 2 divisors, whose sum is σ = 1801201952. Its totient is φ = 1801201950.

The previous prime is 1801201949. The next prime is 1801201993. The reversal of 1801201951 is 1591021081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1801201951 - 2¹ = 1801201949 is a prime.

Together with 1801201949, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1801205951) 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 as a sum of consecutive naturals, namely, 900600975 + 900600976.

It is an arithmetic number, because the mean of its divisors is an integer number (900600976).

Almost surely, 2^1801201951 is an apocalyptic number.

1801201951 is a deficient number, since it is larger than the sum of its proper divisors (1).

1801201951 is an equidigital number, since it uses as much as digits as its factorization.

1801201951 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 28.

The square root of 1801201951 is about 42440.5696356682. The cubic root of 1801201951 is about 1216.7110984545.

The spelling of 1801201951 in words is "one billion, eight hundred one million, two hundred one thousand, nine hundred fifty-one".