642675381 has 8 divisors (see below), whose sum is σ = 859951104. Its totient is φ = 426924960.

The previous prime is 642675379. The next prime is 642675413. The reversal of 642675381 is 183576246.

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

It is not a de Polignac number, because 642675381 - 2¹ = 642675379 is a prime.

It is a super-2 number, since 2×642675381² = 826063290686990322, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642675181) 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, 380341 + ... + 382026.

It is an arithmetic number, because the mean of its divisors is an integer number (107493888).

Almost surely, 2^642675381 is an apocalyptic number.

It is an amenable number.

642675381 is a deficient number, since it is larger than the sum of its proper divisors (217275723).

642675381 is a wasteful number, since it uses less digits than its factorization.

642675381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762651.

The product of its digits is 241920, while the sum is 42.

The square root of 642675381 is about 25351.0429962950. The cubic root of 642675381 is about 862.9730261402.

The spelling of 642675381 in words is "six hundred forty-two million, six hundred seventy-five thousand, three hundred eighty-one".