20005751778 has 16 divisors (see below), whose sum is σ = 41092896000. Its totient is φ = 6488351856.

The previous prime is 20005751767. The next prime is 20005751789. The reversal of 20005751778 is 87715750002.

It is an interprime number because it is at equal distance from previous prime (20005751767) and next prime (20005751789).

It is a super-2 number, since 2×20005751778² (a number of 21 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, 45057778 + ... + 45058221.

It is an arithmetic number, because the mean of its divisors is an integer number (2568306000).

Almost surely, 2^20005751778 is an apocalyptic number.

20005751778 is an abundant number, since it is smaller than the sum of its proper divisors (21087144222).

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

20005751778 is a wasteful number, since it uses less digits than its factorization.

20005751778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90116041.

The product of its (nonzero) digits is 137200, while the sum is 42.

The spelling of 20005751778 in words is "twenty billion, five million, seven hundred fifty-one thousand, seven hundred seventy-eight".