1721137955825 has 12 divisors (see below), whose sum is σ = 2169198133788. Its totient is φ = 1354338062400.

The previous prime is 1721137955821. The next prime is 1721137955833. The reversal of 1721137955825 is 5285597311271.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 826759203169 + 894378752656 = 909263^2 + 945716^2 .

It is not a de Polignac number, because 1721137955825 - 2² = 1721137955821 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1721137955821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 564306002 + ... + 564309051.

It is an arithmetic number, because the mean of its divisors is an integer number (180766511149).

Almost surely, 2^{1721137955825} is an apocalyptic number.

It is an amenable number.

1721137955825 is a deficient number, since it is larger than the sum of its proper divisors (448060177963).

1721137955825 is a wasteful number, since it uses less digits than its factorization.

1721137955825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1128615124 (or 1128615119 counting only the distinct ones).

The product of its digits is 5292000, while the sum is 56.

The spelling of 1721137955825 in words is "one trillion, seven hundred twenty-one billion, one hundred thirty-seven million, nine hundred fifty-five thousand, eight hundred twenty-five".