16405961 has 16 divisors (see below), whose sum is σ = 19692288. Its totient is φ = 13468800.

The previous prime is 16405951. The next prime is 16405997. The reversal of 16405961 is 16950461.

It is a cyclic number.

It is not a de Polignac number, because 16405961 - 2⁶ = 16405897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16405931) 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, 5501 + ... + 7941.

It is an arithmetic number, because the mean of its divisors is an integer number (1230768).

Almost surely, 2^16405961 is an apocalyptic number.

16405961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16405961 is a deficient number, since it is larger than the sum of its proper divisors (3286327).

16405961 is a wasteful number, since it uses less digits than its factorization.

16405961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2512.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 16405961 is about 4050.4272614133. The cubic root of 16405961 is about 254.0975971896.

The spelling of 16405961 in words is "sixteen million, four hundred five thousand, nine hundred sixty-one".