1721540671425 has 36 divisors (see below), whose sum is σ = 3101934588480. Its totient is φ = 912657070560.

The previous prime is 1721540671399. The next prime is 1721540671427. The reversal of 1721540671425 is 5241760451271.

1721540671425 is a `hidden beast` number, since 1 + 7 + 2 + 1 + 540 + 67 + 1 + 42 + 5 = 666.

It is not a de Polignac number, because 1721540671425 - 2¹⁹ = 1721540147137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1721540671427) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 22870485 + ... + 22945634.

It is an arithmetic number, because the mean of its divisors is an integer number (86164849680).

Almost surely, 2^{1721540671425} is an apocalyptic number.

1721540671425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1721540671425 is a deficient number, since it is larger than the sum of its proper divisors (1380393917055).

1721540671425 is a wasteful number, since it uses less digits than its factorization.

1721540671425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45816302 (or 45816294 counting only the distinct ones).

The product of its (nonzero) digits is 470400, while the sum is 45.

The spelling of 1721540671425 in words is "one trillion, seven hundred twenty-one billion, five hundred forty million, six hundred seventy-one thousand, four hundred twenty-five".