21178980900 has 945 divisors, whose sum is σ = 88357749473. Its totient is φ = 4400827200.

The previous prime is 21178980847. The next prime is 21178980913. The reversal of 21178980900 is 908987112.

21178980900 = 1³ + 2³ + ... + 539³.

The square root of 21178980900 is 145530.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 7624433124 + 13554547776 = 87318^2 + 116424^2 .

It is a tau number, because it is divible by the number of its divisors (945).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 314 ways as a sum of consecutive naturals, for example, 1925361895 + ... + 1925361905.

Almost surely, 2^21178980900 is an apocalyptic number.

21178980900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21178980900 is the 145530-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21178980900

21178980900 is an abundant number, since it is smaller than the sum of its proper divisors (67178768573).

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

21178980900 is an equidigital number, since it uses as much as digits as its factorization.

21178980900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The spelling of 21178980900 in words is "twenty-one billion, one hundred seventy-eight million, nine hundred eighty thousand, nine hundred".