541501991 has 2 divisors, whose sum is σ = 541501992. Its totient is φ = 541501990.

The previous prime is 541501981. The next prime is 541502011. The reversal of 541501991 is 199105145.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-541501991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (541501931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 270750995 + 270750996.

It is an arithmetic number, because the mean of its divisors is an integer number (270750996).

Almost surely, 2^541501991 is an apocalyptic number.

541501991 is a deficient number, since it is larger than the sum of its proper divisors (1).

541501991 is an equidigital number, since it uses as much as digits as its factorization.

541501991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8100, while the sum is 35.

The square root of 541501991 is about 23270.1953365244. The cubic root of 541501991 is about 815.0795917602.

The spelling of 541501991 in words is "five hundred forty-one million, five hundred one thousand, nine hundred ninety-one".