20428155772 has 6 divisors (see below), whose sum is σ = 35749272608. Its totient is φ = 10214077884.

The previous prime is 20428155763. The next prime is 20428155773. The reversal of 20428155772 is 27755182402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428155773) by changing a digit.

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 as a sum of consecutive naturals, namely, 2553519468 + ... + 2553519475.

Almost surely, 2^20428155772 is an apocalyptic number.

It is an amenable number.

20428155772 is a deficient number, since it is larger than the sum of its proper divisors (15321116836).

20428155772 is a wasteful number, since it uses less digits than its factorization.

20428155772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5107038947 (or 5107038945 counting only the distinct ones).

The product of its (nonzero) digits is 313600, while the sum is 43.

The spelling of 20428155772 in words is "twenty billion, four hundred twenty-eight million, one hundred fifty-five thousand, seven hundred seventy-two".