1997240521 has 8 divisors (see below), whose sum is σ = 2005907904. Its totient is φ = 1988585040.

The previous prime is 1997240519. The next prime is 1997240533. The reversal of 1997240521 is 1250427991.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1997240521 - 2¹ = 1997240519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1997240591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 520791 + ... + 524611.

It is an arithmetic number, because the mean of its divisors is an integer number (250738488).

Almost surely, 2^1997240521 is an apocalyptic number.

It is an amenable number.

1997240521 is a deficient number, since it is larger than the sum of its proper divisors (8667383).

1997240521 is a wasteful number, since it uses less digits than its factorization.

1997240521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5951.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 1997240521 is about 44690.4969876147. The cubic root of 1997240521 is about 1259.3413289119.

The spelling of 1997240521 in words is "one billion, nine hundred ninety-seven million, two hundred forty thousand, five hundred twenty-one".