21694974 has 32 divisors (see below), whose sum is σ = 49908480. Its totient is φ = 6158592.

The previous prime is 21694951. The next prime is 21694991. The reversal of 21694974 is 47949612.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a congruent 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, 5262 + ... + 8430.

It is an arithmetic number, because the mean of its divisors is an integer number (1559640).

Almost surely, 2^21694974 is an apocalyptic number.

21694974 is an abundant number, since it is smaller than the sum of its proper divisors (28213506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21694974 is a wasteful number, since it uses less digits than its factorization.

21694974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3344.

The product of its digits is 108864, while the sum is 42.

The square root of 21694974 is about 4657.7863841099. The cubic root of 21694974 is about 278.9029093959.

The spelling of 21694974 in words is "twenty-one million, six hundred ninety-four thousand, nine hundred seventy-four".