721027428 has 48 divisors (see below), whose sum is σ = 1931946240. Its totient is φ = 206992800.

The previous prime is 721027379. The next prime is 721027429. The reversal of 721027428 is 824720127.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (721027429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141238 + ... + 146253.

It is an arithmetic number, because the mean of its divisors is an integer number (40248880).

Almost surely, 2^721027428 is an apocalyptic number.

It is an amenable number.

721027428 is an abundant number, since it is smaller than the sum of its proper divisors (1210918812).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721027428 is a wasteful number, since it uses less digits than its factorization.

721027428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287528 (or 287526 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 33.

The square root of 721027428 is about 26851.9538953872. The cubic root of 721027428 is about 896.7070726776.

The spelling of 721027428 in words is "seven hundred twenty-one million, twenty-seven thousand, four hundred twenty-eight".