2001578101 has 2 divisors, whose sum is σ = 2001578102. Its totient is φ = 2001578100.

The previous prime is 2001578077. The next prime is 2001578107. The reversal of 2001578101 is 1018751002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1088934001 + 912644100 = 32999^2 + 30210^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001578101 - 2¹⁵ = 2001545333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001578107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000789050 + 1000789051.

It is an arithmetic number, because the mean of its divisors is an integer number (1000789051).

Almost surely, 2^2001578101 is an apocalyptic number.

It is an amenable number.

2001578101 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001578101 is an equidigital number, since it uses as much as digits as its factorization.

2001578101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 560, while the sum is 25.

The square root of 2001578101 is about 44738.9997764814. Note that the first 3 decimals coincide. The cubic root of 2001578101 is about 1260.2523432192.

The spelling of 2001578101 in words is "two billion, one million, five hundred seventy-eight thousand, one hundred one".