5991961 has 2 divisors, whose sum is σ = 5991962. Its totient is φ = 5991960.

The previous prime is 5991949. The next prime is 5991967. The reversal of 5991961 is 1691995.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5784025 + 207936 = 2405^2 + 456^2 .

It is a cyclic number.

It is not a de Polignac number, because 5991961 - 2⁷ = 5991833 is a prime.

It is a Chen prime.

It is an Ulam number.

5991961 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (5991967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2995980 + 2995981.

It is an arithmetic number, because the mean of its divisors is an integer number (2995981).

Almost surely, 2^5991961 is an apocalyptic number.

It is an amenable number.

5991961 is a deficient number, since it is larger than the sum of its proper divisors (1).

5991961 is an equidigital number, since it uses as much as digits as its factorization.

5991961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21870, while the sum is 40.

The square root of 5991961 is about 2447.8482387599. The cubic root of 5991961 is about 181.6308683870.

The spelling of 5991961 in words is "five million, nine hundred ninety-one thousand, nine hundred sixty-one".