21976705 has 16 divisors (see below), whose sum is σ = 27261504. Its totient is φ = 16994880.

The previous prime is 21976687. The next prime is 21976727. The reversal of 21976705 is 50767912.

It is not a de Polignac number, because 21976705 - 2¹¹ = 21974657 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

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, 38754 + ... + 39316.

It is an arithmetic number, because the mean of its divisors is an integer number (1703844).

Almost surely, 2^21976705 is an apocalyptic number.

It is an amenable number.

21976705 is a deficient number, since it is larger than the sum of its proper divisors (5284799).

21976705 is a wasteful number, since it uses less digits than its factorization.

21976705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816.

The product of its (nonzero) digits is 26460, while the sum is 37.

The square root of 21976705 is about 4687.9318467742. The cubic root of 21976705 is about 280.1049988862.

The spelling of 21976705 in words is "twenty-one million, nine hundred seventy-six thousand, seven hundred five".