16451507772721 has 16 divisors (see below), whose sum is σ = 18905842123776. Its totient is φ = 14023343241936.

The previous prime is 16451507772703. The next prime is 16451507772767. The reversal of 16451507772721 is 12727770515461.

It is not a de Polignac number, because 16451507772721 - 2¹³ = 16451507764529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16451507772121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4426731 + ... + 7245616.

It is an arithmetic number, because the mean of its divisors is an integer number (1181615132736).

Almost surely, 2^{16451507772721} is an apocalyptic number.

It is an amenable number.

16451507772721 is a deficient number, since it is larger than the sum of its proper divisors (2454334351055).

16451507772721 is a wasteful number, since it uses less digits than its factorization.

16451507772721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11673468.

The product of its (nonzero) digits is 5762400, while the sum is 55.

The spelling of 16451507772721 in words is "sixteen trillion, four hundred fifty-one billion, five hundred seven million, seven hundred seventy-two thousand, seven hundred twenty-one".