1072403721 has 12 divisors (see below), whose sum is σ = 1553185348. Its totient is φ = 713016864.

The previous prime is 1072403701. The next prime is 1072403737. The reversal of 1072403721 is 1273042701.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 301508496 + 770895225 = 17364^2 + 27765^2 .

It is not a de Polignac number, because 1072403721 - 2⁷ = 1072403593 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1072403701) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156370 + ... + 163083.

Almost surely, 2^1072403721 is an apocalyptic number.

It is an amenable number.

1072403721 is a deficient number, since it is larger than the sum of its proper divisors (480781627).

1072403721 is a wasteful number, since it uses less digits than its factorization.

1072403721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319832 (or 319829 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 1072403721 is about 32747.5758034087. The cubic root of 1072403721 is about 1023.5744516895.

The spelling of 1072403721 in words is "one billion, seventy-two million, four hundred three thousand, seven hundred twenty-one".