21969974 has 8 divisors (see below), whose sum is σ = 35490000. Its totient is φ = 10139976.

The previous prime is 21969919. The next prime is 21969977. The reversal of 21969974 is 47996912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21969977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 422474 + ... + 422525.

It is an arithmetic number, because the mean of its divisors is an integer number (4436250).

Almost surely, 2^21969974 is an apocalyptic number.

21969974 is a deficient number, since it is larger than the sum of its proper divisors (13520026).

21969974 is a wasteful number, since it uses less digits than its factorization.

21969974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 845014.

The product of its digits is 244944, while the sum is 47.

The square root of 21969974 is about 4687.2138846014. The cubic root of 21969974 is about 280.0763992203.

The spelling of 21969974 in words is "twenty-one million, nine hundred sixty-nine thousand, nine hundred seventy-four".