21345929 has 16 divisors (see below), whose sum is σ = 24131520. Its totient is φ = 18711360.

The previous prime is 21345923. The next prime is 21345959. The reversal of 21345929 is 92954312.

It is a cyclic number.

It is not a de Polignac number, because 21345929 - 2¹² = 21341833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21345923) 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, 72707 + ... + 72999.

It is an arithmetic number, because the mean of its divisors is an integer number (1508220).

Almost surely, 2^21345929 is an apocalyptic number.

It is an amenable number.

21345929 is a deficient number, since it is larger than the sum of its proper divisors (2785591).

21345929 is a wasteful number, since it uses less digits than its factorization.

21345929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520.

The product of its digits is 19440, while the sum is 35.

The square root of 21345929 is about 4620.1654732271. The cubic root of 21345929 is about 277.3990824232.

The spelling of 21345929 in words is "twenty-one million, three hundred forty-five thousand, nine hundred twenty-nine".