642915049920 has 1344 divisors, whose sum is σ = 2555962335360. Its totient is φ = 135795179520.

The previous prime is 642915049919. The next prime is 642915049921. The reversal of 642915049920 is 29940519246.

It is an interprime number because it is at equal distance from previous prime (642915049919) and next prime (642915049921).

It is a super-2 number, since 2×642915049920² (a number of 24 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642915049921) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2320992822 + ... + 2320993098.

It is an arithmetic number, because the mean of its divisors is an integer number (1901757690).

Almost surely, 2^642915049920 is an apocalyptic number.

642915049920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642915049920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1277981167680).

642915049920 is an abundant number, since it is smaller than the sum of its proper divisors (1913047285440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642915049920 is a wasteful number, since it uses less digits than its factorization.

642915049920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414 (or 393 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 51.

The spelling of 642915049920 in words is "six hundred forty-two billion, nine hundred fifteen million, forty-nine thousand, nine hundred twenty".