20645474 has 8 divisors (see below), whose sum is σ = 31147740. Its totient is φ = 10262896.

The previous prime is 20645453. The next prime is 20645483. The reversal of 20645474 is 47454602.

It can be written as a sum of positive squares in 2 ways, for example, as 17430625 + 3214849 = 4175^2 + 1793^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 20645474.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29489 + ... + 30180.

Almost surely, 2^20645474 is an apocalyptic number.

20645474 is a deficient number, since it is larger than the sum of its proper divisors (10502266).

20645474 is a wasteful number, since it uses less digits than its factorization.

20645474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59844.

The product of its (nonzero) digits is 26880, while the sum is 32.

The square root of 20645474 is about 4543.7290852338. The cubic root of 20645474 is about 274.3310417969.

The spelling of 20645474 in words is "twenty million, six hundred forty-five thousand, four hundred seventy-four".