721861466 has 4 divisors (see below), whose sum is σ = 1082792202. Its totient is φ = 360930732.

The previous prime is 721861451. The next prime is 721861477. The reversal of 721861466 is 664168127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 664168127 = 7 ⋅94881161.

It can be written as a sum of positive squares in only one way, i.e., 623950441 + 97911025 = 24979^2 + 9895^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180465365 + ... + 180465368.

Almost surely, 2^721861466 is an apocalyptic number.

721861466 is a deficient number, since it is larger than the sum of its proper divisors (360930736).

721861466 is a wasteful number, since it uses less digits than its factorization.

721861466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360930735.

The product of its digits is 96768, while the sum is 41.

The square root of 721861466 is about 26867.4797106093. The cubic root of 721861466 is about 897.0526904078.

The spelling of 721861466 in words is "seven hundred twenty-one million, eight hundred sixty-one thousand, four hundred sixty-six".