997874640 has 240 divisors, whose sum is σ = 3972329088. Its totient is φ = 228054528.

The previous prime is 997874639. The next prime is 997874651. The reversal of 997874640 is 46478799.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 132414 + ... + 139746.

Almost surely, 2^997874640 is an apocalyptic number.

997874640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997874640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1986164544).

997874640 is an abundant number, since it is smaller than the sum of its proper divisors (2974454448).

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

997874640 is a wasteful number, since it uses less digits than its factorization.

997874640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7368 (or 7350 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 54.

The square root of 997874640 is about 31589.1538348212. The cubic root of 997874640 is about 999.2910441671.

The spelling of 997874640 in words is "nine hundred ninety-seven million, eight hundred seventy-four thousand, six hundred forty".