21192146640 has 1120 divisors, whose sum is σ = 91962256896. Its totient is φ = 4434186240.

The previous prime is 21192146597. The next prime is 21192146687. The reversal of 21192146640 is 4664129112.

21192146640 is a `hidden beast` number, since 2 + 1 + 1 + 9 + 2 + 1 + 4 + 6 + 640 = 666.

It is a super-2 number, since 2×21192146640² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21192146595 and 21192146604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 347412210 + ... + 347412270.

Almost surely, 2^21192146640 is an apocalyptic number.

21192146640 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 21192146640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45981128448).

21192146640 is an abundant number, since it is smaller than the sum of its proper divisors (70770110256).

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

21192146640 is a wasteful number, since it uses less digits than its factorization.

21192146640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 21192146640 in words is "twenty-one billion, one hundred ninety-two million, one hundred forty-six thousand, six hundred forty".