721777534077772 has 6 divisors (see below), whose sum is σ = 1263110684636108. Its totient is φ = 360888767038884.

The previous prime is 721777534077727. The next prime is 721777534077793. The reversal of 721777534077772 is 277770435777127.

It is a junction number, because it is equal to n+sod(n) for n = 721777534077695 and 721777534077704.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90222191759718 + ... + 90222191759725.

Almost surely, 2^{721777534077772} is an apocalyptic number.

It is an amenable number.

721777534077772 is a deficient number, since it is larger than the sum of its proper divisors (541333150558336).

721777534077772 is a wasteful number, since it uses less digits than its factorization.

721777534077772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180444383519447 (or 180444383519445 counting only the distinct ones).

The product of its (nonzero) digits is 1383552240, while the sum is 73.

The spelling of 721777534077772 in words is "seven hundred twenty-one trillion, seven hundred seventy-seven billion, five hundred thirty-four million, seventy-seven thousand, seven hundred seventy-two".