21931834 has 16 divisors (see below), whose sum is σ = 34914240. Its totient is φ = 10310080.

The previous prime is 21931823. The next prime is 21931841. The reversal of 21931834 is 43813912.

It is a junction number, because it is equal to n+sod(n) for n = 21931796 and 21931805.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1327 + ... + 6754.

It is an arithmetic number, because the mean of its divisors is an integer number (2182140).

Almost surely, 2^21931834 is an apocalyptic number.

21931834 is a deficient number, since it is larger than the sum of its proper divisors (12982406).

21931834 is a wasteful number, since it uses less digits than its factorization.

21931834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8165.

The product of its digits is 5184, while the sum is 31.

The square root of 21931834 is about 4683.1436023253. The cubic root of 21931834 is about 279.9142339360.

The spelling of 21931834 in words is "twenty-one million, nine hundred thirty-one thousand, eight hundred thirty-four".