20400420642 has 32 divisors (see below), whose sum is σ = 46677648384. Its totient is φ = 5822677200.

The previous prime is 20400420617. The next prime is 20400420643. The reversal of 20400420642 is 24602400402.

It is not an unprimeable number, because it can be changed into a prime (20400420643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209334 + ... + 290897.

It is an arithmetic number, because the mean of its divisors is an integer number (1458676512).

Almost surely, 2^20400420642 is an apocalyptic number.

20400420642 is an abundant number, since it is smaller than the sum of its proper divisors (26277227742).

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

20400420642 is a wasteful number, since it uses less digits than its factorization.

20400420642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501214.

The product of its (nonzero) digits is 3072, while the sum is 24.

The spelling of 20400420642 in words is "twenty billion, four hundred million, four hundred twenty thousand, six hundred forty-two".