19655402340 has 480 divisors, whose sum is σ = 69568773120. Its totient is φ = 4132332288.

The previous prime is 19655402317. The next prime is 19655402369. The reversal of 19655402340 is 4320455691.

It is a super-2 number, since 2×19655402340² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 117696937 + ... + 117697103.

It is an arithmetic number, because the mean of its divisors is an integer number (144934944).

Almost surely, 2^19655402340 is an apocalyptic number.

19655402340 is a gapful number since it is divisible by the number (10) 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 19655402340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34784386560).

19655402340 is an abundant number, since it is smaller than the sum of its proper divisors (49913370780).

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

19655402340 is a wasteful number, since it uses less digits than its factorization.

19655402340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 246 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 39.

The spelling of 19655402340 in words is "nineteen billion, six hundred fifty-five million, four hundred two thousand, three hundred forty".