20763766778640 has 40 divisors (see below), whose sum is σ = 64367677014528. Its totient is φ = 5537004474240.

The previous prime is 20763766778639. The next prime is 20763766778687. The reversal of 20763766778640 is 4687766736702.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×20763766778640² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43257847216 + ... + 43257847695.

Almost surely, 2^{20763766778640} is an apocalyptic number.

20763766778640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20763766778640 is an abundant number, since it is smaller than the sum of its proper divisors (43603910235888).

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

20763766778640 is a wasteful number, since it uses less digits than its factorization.

20763766778640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86515694927 (or 86515694921 counting only the distinct ones).

The product of its (nonzero) digits is 597445632, while the sum is 69.

The spelling of 20763766778640 in words is "twenty trillion, seven hundred sixty-three billion, seven hundred sixty-six million, seven hundred seventy-eight thousand, six hundred forty".