721341045 has 20 divisors (see below), whose sum is σ = 1293071340. Its totient is φ = 384715008.

The previous prime is 721341029. The next prime is 721341073. The reversal of 721341045 is 540143127.

It can be written as a sum of positive squares in 2 ways, for example, as 447703281 + 273637764 = 21159^2 + 16542^2 .

It is not a de Polignac number, because 721341045 - 2⁴ = 721341029 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 890140 + ... + 890949.

It is an arithmetic number, because the mean of its divisors is an integer number (64653567).

Almost surely, 2^721341045 is an apocalyptic number.

It is an amenable number.

721341045 is a deficient number, since it is larger than the sum of its proper divisors (571730295).

721341045 is a wasteful number, since it uses less digits than its factorization.

721341045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781106 (or 1781097 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 721341045 is about 26857.7930031490. The cubic root of 721341045 is about 896.8370639500.

The spelling of 721341045 in words is "seven hundred twenty-one million, three hundred forty-one thousand, forty-five".