72021405 has 16 divisors (see below), whose sum is σ = 115539840. Its totient is φ = 38309568.

The previous prime is 72021373. The next prime is 72021473. The reversal of 72021405 is 50412027.

It is not a de Polignac number, because 72021405 - 2⁵ = 72021373 is a prime.

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, 337 + ... + 12006.

It is an arithmetic number, because the mean of its divisors is an integer number (7221240).

Almost surely, 2^72021405 is an apocalyptic number.

It is an amenable number.

72021405 is a deficient number, since it is larger than the sum of its proper divisors (43518435).

72021405 is a wasteful number, since it uses less digits than its factorization.

72021405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12740.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 72021405 is about 8486.5425822298. The cubic root of 72021405 is about 416.0579866314.

The spelling of 72021405 in words is "seventy-two million, twenty-one thousand, four hundred five".