20472742 has 4 divisors (see below), whose sum is σ = 30709116. Its totient is φ = 10236370.

The previous prime is 20472733. The next prime is 20472757. The reversal of 20472742 is 24727402.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20472742.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5118184 + ... + 5118187.

It is an arithmetic number, because the mean of its divisors is an integer number (7677279).

Almost surely, 2^20472742 is an apocalyptic number.

20472742 is a deficient number, since it is larger than the sum of its proper divisors (10236374).

20472742 is a wasteful number, since it uses less digits than its factorization.

20472742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10236373.

The product of its (nonzero) digits is 6272, while the sum is 28.

The square root of 20472742 is about 4524.6814252497. The cubic root of 20472742 is about 273.5638273229.

It can be divided in two parts, 2047274 and 2, that added together give a triangular number (2047276 = T₂₀₂₃).

The spelling of 20472742 in words is "twenty million, four hundred seventy-two thousand, seven hundred forty-two".