20694397680 has 360 divisors, whose sum is σ = 79034941440. Its totient is φ = 4843238400.

The previous prime is 20694397663. The next prime is 20694397799. The reversal of 20694397680 is 8679349602.

It is a happy number.

20694397680 is a `hidden beast` number, since 2 + 0 + 69 + 439 + 76 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2522385 + ... + 2530575.

It is an arithmetic number, because the mean of its divisors is an integer number (219541504).

Almost surely, 2^20694397680 is an apocalyptic number.

20694397680 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 20694397680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39517470720).

20694397680 is an abundant number, since it is smaller than the sum of its proper divisors (58340543760).

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

20694397680 is a wasteful number, since it uses less digits than its factorization.

20694397680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8261 (or 8241 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 54.

The spelling of 20694397680 in words is "twenty billion, six hundred ninety-four million, three hundred ninety-seven thousand, six hundred eighty".