1997940769 has 8 divisors (see below), whose sum is σ = 2180481408. Its totient is φ = 1815551760.

The previous prime is 1997940767. The next prime is 1997940803. The reversal of 1997940769 is 9670497991.

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

It is not a de Polignac number, because 1997940769 - 2¹ = 1997940767 is a prime.

It is a super-2 number, since 2×1997940769² = 7983534632864622722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1997940767) 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, 9417 + ... + 63910.

It is an arithmetic number, because the mean of its divisors is an integer number (272560176).

Almost surely, 2^1997940769 is an apocalyptic number.

It is an amenable number.

1997940769 is a deficient number, since it is larger than the sum of its proper divisors (182540639).

1997940769 is a wasteful number, since it uses less digits than its factorization.

1997940769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75815.

The product of its (nonzero) digits is 7715736, while the sum is 61.

The square root of 1997940769 is about 44698.3307182718. The cubic root of 1997940769 is about 1259.4884899902.

The spelling of 1997940769 in words is "one billion, nine hundred ninety-seven million, nine hundred forty thousand, seven hundred sixty-nine".