72121070 has 32 divisors (see below), whose sum is σ = 149846976. Its totient is φ = 24482400.

The previous prime is 72121067. The next prime is 72121081. The reversal of 72121070 is 7012127.

It is a Smith number, since the sum of its digits (20) coincides with the sum of the digits of its prime factors.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 714020 + ... + 714120.

It is an arithmetic number, because the mean of its divisors is an integer number (4682718).

Almost surely, 2^72121070 is an apocalyptic number.

72121070 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

72121070 is an abundant number, since it is smaller than the sum of its proper divisors (77725906).

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

72121070 is an frugal number, since it uses more digits than its factorization.

72121070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 196, while the sum is 20.

The square root of 72121070 is about 8492.4124958695. The cubic root of 72121070 is about 416.2498152807.

Adding to 72121070 its reverse (7012127), we get a palindrome (79133197).

The spelling of 72121070 in words is "seventy-two million, one hundred twenty-one thousand, seventy".