20409796542 has 64 divisors (see below), whose sum is σ = 43658910720. Its totient is φ = 6341981184.

The previous prime is 20409796531. The next prime is 20409796549. The reversal of 20409796542 is 24569790402.

It is a junction number, because it is equal to n+sod(n) for n = 20409796491 and 20409796500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20409796549) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3850438 + ... + 3855734.

It is an arithmetic number, because the mean of its divisors is an integer number (682170480).

Almost surely, 2^20409796542 is an apocalyptic number.

20409796542 is an abundant number, since it is smaller than the sum of its proper divisors (23249114178).

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

20409796542 is a wasteful number, since it uses less digits than its factorization.

20409796542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5857.

The product of its (nonzero) digits is 1088640, while the sum is 48.

The spelling of 20409796542 in words is "twenty billion, four hundred nine million, seven hundred ninety-six thousand, five hundred forty-two".