991946005 has 16 divisors (see below), whose sum is σ = 1291099824. Its totient is φ = 728657920.

The previous prime is 991946003. The next prime is 991946057. The reversal of 991946005 is 500649199.

It can be written as a sum of positive squares in 8 ways, for example, as 14945956 + 977000049 = 3866^2 + 31257^2 .

It is not a de Polignac number, because 991946005 - 2¹ = 991946003 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991946003) 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, 138832 + ... + 145801.

It is an arithmetic number, because the mean of its divisors is an integer number (80693739).

Almost surely, 2^991946005 is an apocalyptic number.

It is an amenable number.

991946005 is a deficient number, since it is larger than the sum of its proper divisors (299153819).

991946005 is a wasteful number, since it uses less digits than its factorization.

991946005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284696.

The product of its (nonzero) digits is 87480, while the sum is 43.

The square root of 991946005 is about 31495.1743129007. The cubic root of 991946005 is about 997.3080951504.

The spelling of 991946005 in words is "nine hundred ninety-one million, nine hundred forty-six thousand, five".