137745415721 has 8 divisors (see below), whose sum is σ = 145854868104. Its totient is φ = 129636716800.

The previous prime is 137745415693. The next prime is 137745415733. The reversal of 137745415721 is 127514547731.

It can be written as a sum of positive squares in 4 ways, for example, as 104823127696 + 32922288025 = 323764^2 + 181445^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-137745415721 is a prime.

It is a super-2 number, since 2×137745415721² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (137745415741) 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 7 ways as a sum of consecutive naturals, for example, 212411 + ... + 566223.

It is an arithmetic number, because the mean of its divisors is an integer number (18231858513).

Almost surely, 2^137745415721 is an apocalyptic number.

It is an amenable number.

137745415721 is a deficient number, since it is larger than the sum of its proper divisors (8109452383).

137745415721 is a wasteful number, since it uses less digits than its factorization.

137745415721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376731.

The product of its digits is 823200, while the sum is 47.

The spelling of 137745415721 in words is "one hundred thirty-seven billion, seven hundred forty-five million, four hundred fifteen thousand, seven hundred twenty-one".