20471644 has 12 divisors (see below), whose sum is σ = 35870800. Its totient is φ = 10222848.

The previous prime is 20471639. The next prime is 20471663. The reversal of 20471644 is 44617402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 892 + ... + 6460.

Almost surely, 2^20471644 is an apocalyptic number.

It is an amenable number.

20471644 is a deficient number, since it is larger than the sum of its proper divisors (15399156).

20471644 is a wasteful number, since it uses less digits than its factorization.

20471644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6492 (or 6490 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 28.

The square root of 20471644 is about 4524.5600891136. The cubic root of 20471644 is about 273.5589366174.

It can be divided in two parts, 20471 and 644, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 20471644 in words is "twenty million, four hundred seventy-one thousand, six hundred forty-four".