72100020 has 48 divisors (see below), whose sum is σ = 202366080. Its totient is φ = 19180416.

The previous prime is 72099997. The next prime is 72100027. The reversal of 72100020 is 2000127.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 72099969 and 72100005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72100027) 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, 28986 + ... + 31374.

It is an arithmetic number, because the mean of its divisors is an integer number (4215960).

Almost surely, 2^72100020 is an apocalyptic number.

It is an amenable number.

72100020 is an abundant number, since it is smaller than the sum of its proper divisors (130266060).

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

72100020 is a wasteful number, since it uses less digits than its factorization.

72100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2904 (or 2902 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 12.

The square root of 72100020 is about 8491.1730638352. The cubic root of 72100020 is about 416.2093143507.

Adding to 72100020 its reverse (2000127), we get a palindrome (74100147).

The spelling of 72100020 in words is "seventy-two million, one hundred thousand, twenty".