20691069408 has 192 divisors, whose sum is σ = 63611956800. Its totient is φ = 6533130240.

The previous prime is 20691069349. The next prime is 20691069433. The reversal of 20691069408 is 80496019602.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1320178 + ... + 1335758.

It is an arithmetic number, because the mean of its divisors is an integer number (331312275).

Almost surely, 2^20691069408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20691069408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31805978400).

20691069408 is an abundant number, since it is smaller than the sum of its proper divisors (42920887392).

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

20691069408 is a wasteful number, since it uses less digits than its factorization.

20691069408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15682 (or 15668 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 20691069408 in words is "twenty billion, six hundred ninety-one million, sixty-nine thousand, four hundred eight".