1966446691 has 16 divisors (see below), whose sum is σ = 2183262048. Its totient is φ = 1756051200.

The previous prime is 1966446689. The next prime is 1966446697.

1966446691 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 1966446691 - 2¹ = 1966446689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1966446697) 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, 691725 + ... + 694561.

It is an arithmetic number, because the mean of its divisors is an integer number (136453878).

Almost surely, 2^1966446691 is an apocalyptic number.

1966446691 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1966446691 is a deficient number, since it is larger than the sum of its proper divisors (216815357).

1966446691 is a wasteful number, since it uses less digits than its factorization.

1966446691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3942.

The product of its digits is 1679616, while the sum is 52.

The square root of 1966446691 is about 44344.6354252687. The cubic root of 1966446691 is about 1252.8355237272.

The spelling of 1966446691 in words is "one billion, nine hundred sixty-six million, four hundred forty-six thousand, six hundred ninety-one".