1997084389391 has 64 divisors (see below), whose sum is σ = 2536443576576. Its totient is φ = 1530250444800.

The previous prime is 1997084389369. The next prime is 1997084389409. The reversal of 1997084389391 is 1939834807991.

It is not a de Polignac number, because 1997084389391 - 2¹⁴ = 1997084373007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997084389591) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 416664491 + ... + 416669283.

It is an arithmetic number, because the mean of its divisors is an integer number (39631930884).

Almost surely, 2^{1997084389391} is an apocalyptic number.

1997084389391 is a deficient number, since it is larger than the sum of its proper divisors (539359187185).

1997084389391 is a wasteful number, since it uses less digits than its factorization.

1997084389391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5652.

The product of its (nonzero) digits is 105815808, while the sum is 71.

The spelling of 1997084389391 in words is "one trillion, nine hundred ninety-seven billion, eighty-four million, three hundred eighty-nine thousand, three hundred ninety-one".