642738471 has 8 divisors (see below), whose sum is σ = 867310080. Its totient is φ = 423329592.

The previous prime is 642738451. The next prime is 642738521. The reversal of 642738471 is 174837246.

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

It is not a de Polignac number, because 642738471 - 2¹³ = 642730279 is a prime.

It is a super-3 number, since 3×642738471³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642738401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1290391 + ... + 1290888.

It is an arithmetic number, because the mean of its divisors is an integer number (108413760).

Almost surely, 2^642738471 is an apocalyptic number.

642738471 is a deficient number, since it is larger than the sum of its proper divisors (224571609).

642738471 is a wasteful number, since it uses less digits than its factorization.

642738471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2581365.

The product of its digits is 225792, while the sum is 42.

The square root of 642738471 is about 25352.2872932601. The cubic root of 642738471 is about 863.0012639247.

The spelling of 642738471 in words is "six hundred forty-two million, seven hundred thirty-eight thousand, four hundred seventy-one".