761991 has 16 divisors (see below), whose sum is σ = 1096704. Its totient is φ = 468864.

The previous prime is 761983. The next prime is 761993. The reversal of 761991 is 199167.

761991 = T₁₃ + T₁₄ + ... + T₁₆₅.

It is not a de Polignac number, because 761991 - 2³ = 761983 is a prime.

761991 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (761993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3306 + ... + 3528.

It is an arithmetic number, because the mean of its divisors is an integer number (68544).

2⁷⁶¹⁹⁹¹ is an apocalyptic number.

761991 is a deficient number, since it is larger than the sum of its proper divisors (334713).

761991 is a wasteful number, since it uses less digits than its factorization.

761991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310.

The product of its digits is 3402, while the sum is 33.

The square root of 761991 is about 872.9209586211. The cubic root of 761991 is about 91.3376739136.

The spelling of 761991 in words is "seven hundred sixty-one thousand, nine hundred ninety-one".