997973780 has 24 divisors (see below), whose sum is σ = 2219024808. Its totient is φ = 375707648.

The previous prime is 997973773. The next prime is 997973827. The reversal of 997973780 is 87379799.

It can be written as a sum of positive squares in 4 ways, for example, as 249513616 + 748460164 = 15796^2 + 27358^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1467269 + ... + 1467948.

It is an arithmetic number, because the mean of its divisors is an integer number (92459367).

Almost surely, 2^997973780 is an apocalyptic number.

It is an amenable number.

997973780 is an abundant number, since it is smaller than the sum of its proper divisors (1221051028).

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

997973780 is a wasteful number, since it uses less digits than its factorization.

997973780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2935243 (or 2935241 counting only the distinct ones).

The product of its (nonzero) digits is 6001128, while the sum is 59.

The square root of 997973780 is about 31590.7230053381. The cubic root of 997973780 is about 999.3241366450.

The spelling of 997973780 in words is "nine hundred ninety-seven million, nine hundred seventy-three thousand, seven hundred eighty".