221400379640 has 64 divisors (see below), whose sum is σ = 572039280000. Its totient is φ = 76271898240.

The previous prime is 221400379633. The next prime is 221400379643. The reversal of 221400379640 is 46973004122.

It is a super-2 number, since 2×221400379640² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 221400379594 and 221400379603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221400379643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13233290 + ... + 13250009.

It is an arithmetic number, because the mean of its divisors is an integer number (8938113750).

Almost surely, 2^221400379640 is an apocalyptic number.

221400379640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221400379640 is an abundant number, since it is smaller than the sum of its proper divisors (350638900360).

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

221400379640 is a wasteful number, since it uses less digits than its factorization.

221400379640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26483340 (or 26483336 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 38.

The spelling of 221400379640 in words is "two hundred twenty-one billion, four hundred million, three hundred seventy-nine thousand, six hundred forty".