72921130 has 8 divisors (see below), whose sum is σ = 131258052. Its totient is φ = 29168448.

The previous prime is 72921119. The next prime is 72921131. The reversal of 72921130 is 3112927.

It can be written as a sum of positive squares in 2 ways, for example, as 70913241 + 2007889 = 8421^2 + 1417^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 72921095 and 72921104.

It is not an unprimeable number, because it can be changed into a prime (72921131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3646047 + ... + 3646066.

Almost surely, 2^72921130 is an apocalyptic number.

72921130 is a deficient number, since it is larger than the sum of its proper divisors (58336922).

72921130 is a wasteful number, since it uses less digits than its factorization.

72921130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7292120.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 72921130 is about 8539.3869803400. The cubic root of 72921130 is about 417.7833519378.

The spelling of 72921130 in words is "seventy-two million, nine hundred twenty-one thousand, one hundred thirty".