16405380 has 36 divisors (see below), whose sum is σ = 49763532. Its totient is φ = 4374720.

The previous prime is 16405373. The next prime is 16405381. The reversal of 16405380 is 8350461.

16405380 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 3617604 + 12787776 = 1902^2 + 3576^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (16405381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45391 + ... + 45750.

Almost surely, 2^16405380 is an apocalyptic number.

16405380 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16405380 is an abundant number, since it is smaller than the sum of its proper divisors (33358152).

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

16405380 is a wasteful number, since it uses less digits than its factorization.

16405380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91156 (or 91151 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 16405380 is about 4050.3555399495. The cubic root of 16405380 is about 254.0945976204.

Subtracting from 16405380 its product of nonzero digits (2880), we obtain a square (16402500 = 4050²).

The spelling of 16405380 in words is "sixteen million, four hundred five thousand, three hundred eighty".