1955781878100 has 288 divisors, whose sum is σ = 6005092316160. Its totient is φ = 490420085760.

The previous prime is 1955781878087. The next prime is 1955781878101. The reversal of 1955781878100 is 18781875591.

It is a super-2 number, since 2×1955781878100² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1955781878101) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 241778856 + ... + 241786944.

Almost surely, 2^{1955781878100} is an apocalyptic number.

1955781878100 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 1955781878100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3002546158080).

1955781878100 is an abundant number, since it is smaller than the sum of its proper divisors (4049310438060).

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

1955781878100 is a wasteful number, since it uses less digits than its factorization.

1955781878100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8719 (or 8712 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 60.

The spelling of 1955781878100 in words is "one trillion, nine hundred fifty-five billion, seven hundred eighty-one million, eight hundred seventy-eight thousand, one hundred".