164390440 has 16 divisors (see below), whose sum is σ = 369878580. Its totient is φ = 65756160.

The previous prime is 164390437. The next prime is 164390441. The reversal of 164390440 is 44093461.

It can be written as a sum of positive squares in 2 ways, for example, as 164198596 + 191844 = 12814^2 + 438^2 .

It is not an unprimeable number, because it can be changed into a prime (164390441) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2054841 + ... + 2054920.

Almost surely, 2^164390440 is an apocalyptic number.

164390440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

164390440 is an abundant number, since it is smaller than the sum of its proper divisors (205488140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

164390440 is a wasteful number, since it uses less digits than its factorization.

164390440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4109772 (or 4109768 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 164390440 is about 12821.4835335073. The cubic root of 164390440 is about 547.8044038836.

The spelling of 164390440 in words is "one hundred sixty-four million, three hundred ninety thousand, four hundred forty".