221956079100 has 864 divisors, whose sum is σ = 827634528000. Its totient is φ = 45600952320.

The previous prime is 221956079087. The next prime is 221956079101. The reversal of 221956079100 is 1970659122.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221956079101) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 542679696 + ... + 542680104.

Almost surely, 2^221956079100 is an apocalyptic number.

221956079100 is a gapful number since it is divisible by the number (20) 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 221956079100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (413817264000).

221956079100 is an abundant number, since it is smaller than the sum of its proper divisors (605678448900).

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

221956079100 is a wasteful number, since it uses less digits than its factorization.

221956079100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 555 (or 541 counting only the distinct ones).

The product of its (nonzero) digits is 68040, while the sum is 42.

The spelling of 221956079100 in words is "two hundred twenty-one billion, nine hundred fifty-six million, seventy-nine thousand, one hundred".