1999018061 has 2 divisors, whose sum is σ = 1999018062. Its totient is φ = 1999018060.

The previous prime is 1999018037. The next prime is 1999018081. The reversal of 1999018061 is 1608109991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1048529161 + 950488900 = 32381^2 + 30830^2 .

It is an emirp because it is prime and its reverse (1608109991) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 1908106661 and 1666018091.

It is a cyclic number.

It is not a de Polignac number, because 1999018061 - 2³⁰ = 925276237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1999018031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999509030 + 999509031.

It is an arithmetic number, because the mean of its divisors is an integer number (999509031).

Almost surely, 2^1999018061 is an apocalyptic number.

It is an amenable number.

1999018061 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999018061 is an equidigital number, since it uses as much as digits as its factorization.

1999018061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 44.

The square root of 1999018061 is about 44710.3797903798. The cubic root of 1999018061 is about 1259.7148218713.

The spelling of 1999018061 in words is "one billion, nine hundred ninety-nine million, eighteen thousand, sixty-one".