997645740 has 192 divisors, whose sum is σ = 3486529536. Its totient is φ = 207525888.

The previous prime is 997645729. The next prime is 997645777. The reversal of 997645740 is 47546799.

It is a super-3 number, since 3×997645740³ (a number of 28 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 397329 + ... + 399831.

It is an arithmetic number, because the mean of its divisors is an integer number (18159008).

Almost surely, 2^997645740 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997645740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1743264768).

997645740 is an abundant number, since it is smaller than the sum of its proper divisors (2488883796).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

997645740 is a wasteful number, since it uses less digits than its factorization.

997645740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2608 (or 2606 counting only the distinct ones).

The product of its (nonzero) digits is 1905120, while the sum is 51.

The square root of 997645740 is about 31585.5305480215. The cubic root of 997645740 is about 999.2146300221.

The spelling of 997645740 in words is "nine hundred ninety-seven million, six hundred forty-five thousand, seven hundred forty".