721900429 has 4 divisors (see below), whose sum is σ = 729048060. Its totient is φ = 714752800.

The previous prime is 721900423. The next prime is 721900447. The reversal of 721900429 is 924009127.

It is a happy number.

721900429 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 924009127 = 67 ⋅13791181.

It can be written as a sum of positive squares in 2 ways, for example, as 670706404 + 51194025 = 25898^2 + 7155^2 .

It is a cyclic number.

It is not a de Polignac number, because 721900429 - 2¹⁹ = 721376141 is a prime.

It is a super-2 number, since 2×721900429² = 1042280458780768082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 721900394 and 721900403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721900423) 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, 3573664 + ... + 3573865.

It is an arithmetic number, because the mean of its divisors is an integer number (182262015).

Almost surely, 2^721900429 is an apocalyptic number.

It is an amenable number.

721900429 is a deficient number, since it is larger than the sum of its proper divisors (7147631).

721900429 is a wasteful number, since it uses less digits than its factorization.

721900429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7147630.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 721900429 is about 26868.2047967481. The cubic root of 721900429 is about 897.0688298088.

The spelling of 721900429 in words is "seven hundred twenty-one million, nine hundred thousand, four hundred twenty-nine".