642370155643221 has 8 divisors (see below), whose sum is σ = 857601553203360. Its totient is φ = 427692764255952.

The previous prime is 642370155643199. The next prime is 642370155643277. The reversal of 642370155643221 is 122346551073246.

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

It is not a de Polignac number, because 642370155643221 - 2²⁶ = 642370088534357 is a prime.

It is a super-2 number, since 2×642370155643221² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642370155643621) 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, 138501540511 + ... + 138501545148.

It is an arithmetic number, because the mean of its divisors is an integer number (107200194150420).

Almost surely, 2^{642370155643221} is an apocalyptic number.

It is an amenable number.

642370155643221 is a deficient number, since it is larger than the sum of its proper divisors (215231397560139).

642370155643221 is a wasteful number, since it uses less digits than its factorization.

642370155643221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277003086435.

The product of its (nonzero) digits is 7257600, while the sum is 51.

The spelling of 642370155643221 in words is "six hundred forty-two trillion, three hundred seventy billion, one hundred fifty-five million, six hundred forty-three thousand, two hundred twenty-one".