721447378 has 8 divisors (see below), whose sum is σ = 1107337968. Its totient is φ = 352334724.

The previous prime is 721447373. The next prime is 721447381. The reversal of 721447378 is 873744127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is not an unprimeable number, because it can be changed into a prime (721447373) 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, 4194376 + ... + 4194547.

It is an arithmetic number, because the mean of its divisors is an integer number (138417246).

Almost surely, 2^721447378 is an apocalyptic number.

721447378 is a deficient number, since it is larger than the sum of its proper divisors (385890590).

721447378 is a wasteful number, since it uses less digits than its factorization.

721447378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8388968.

The product of its digits is 263424, while the sum is 43.

The square root of 721447378 is about 26859.7724860059. The cubic root of 721447378 is about 896.8811294170.

The spelling of 721447378 in words is "seven hundred twenty-one million, four hundred forty-seven thousand, three hundred seventy-eight".