72621220 has 96 divisors (see below), whose sum is σ = 186439680. Its totient is φ = 23224320.

The previous prime is 72621217. The next prime is 72621223. The reversal of 72621220 is 2212627.

It is an interprime number because it is at equal distance from previous prime (72621217) and next prime (72621223).

It is a junction number, because it is equal to n+sod(n) for n = 72621191 and 72621200.

It is not an unprimeable number, because it can be changed into a prime (72621223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125572 + ... + 126148.

It is an arithmetic number, because the mean of its divisors is an integer number (1942080).

Almost surely, 2^72621220 is an apocalyptic number.

72621220 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72621220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93219840).

72621220 is an abundant number, since it is smaller than the sum of its proper divisors (113818460).

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

72621220 is a wasteful number, since it uses less digits than its factorization.

72621220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653 (or 651 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 72621220 is about 8521.8084935065. The cubic root of 72621220 is about 417.2098118541.

Adding to 72621220 its reverse (2212627), we get a palindrome (74833847).

The spelling of 72621220 in words is "seventy-two million, six hundred twenty-one thousand, two hundred twenty".