1987497397 has 8 divisors (see below), whose sum is σ = 2063305440. Its totient is φ = 1912174320.

The previous prime is 1987497371. The next prime is 1987497461. The reversal of 1987497397 is 7937947891.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1987497397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987497097) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112879 + ... + 129292.

It is an arithmetic number, because the mean of its divisors is an integer number (257913180).

Almost surely, 2^1987497397 is an apocalyptic number.

It is an amenable number.

1987497397 is a deficient number, since it is larger than the sum of its proper divisors (75808043).

1987497397 is a wasteful number, since it uses less digits than its factorization.

1987497397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242483.

The product of its digits is 24004512, while the sum is 64.

The square root of 1987497397 is about 44581.3570565096. The cubic root of 1987497397 is about 1257.2901780145.

The spelling of 1987497397 in words is "one billion, nine hundred eighty-seven million, four hundred ninety-seven thousand, three hundred ninety-seven".