72111766420 has 48 divisors (see below), whose sum is σ = 155733128208. Its totient is φ = 28028021760.

The previous prime is 72111766381. The next prime is 72111766423. The reversal of 72111766420 is 2466711127.

It can be written as a sum of positive squares in 8 ways, for example, as 819562384 + 71292204036 = 28628^2 + 267006^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 72111766420.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72111766423) 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, 499114 + ... + 627166.

It is an arithmetic number, because the mean of its divisors is an integer number (3244440171).

Almost surely, 2^72111766420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72111766420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77866564104).

72111766420 is an abundant number, since it is smaller than the sum of its proper divisors (83621361788).

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

72111766420 is a wasteful number, since it uses less digits than its factorization.

72111766420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128860 (or 128858 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 37.

The spelling of 72111766420 in words is "seventy-two billion, one hundred eleven million, seven hundred sixty-six thousand, four hundred twenty".