21346505 has 16 divisors (see below), whose sum is σ = 26210304. Its totient is φ = 16685760.

The previous prime is 21346489. The next prime is 21346513. The reversal of 21346505 is 50564312.

It is not a de Polignac number, because 21346505 - 2⁴ = 21346489 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55544 + ... + 55926.

It is an arithmetic number, because the mean of its divisors is an integer number (1638144).

Almost surely, 2^21346505 is an apocalyptic number.

It is an amenable number.

21346505 is a deficient number, since it is larger than the sum of its proper divisors (4863799).

21346505 is a wasteful number, since it uses less digits than its factorization.

21346505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 616.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 21346505 is about 4620.2278082363. The cubic root of 21346505 is about 277.4015775193.

The spelling of 21346505 in words is "twenty-one million, three hundred forty-six thousand, five hundred five".