79421940 has 72 divisors (see below), whose sum is σ = 259452648. Its totient is φ = 19549440.

The previous prime is 79421933. The next prime is 79421941. The reversal of 79421940 is 4912497.

It can be written as a sum of positive squares in 4 ways, for example, as 1205604 + 78216336 = 1098^2 + 8844^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 79421895 and 79421904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79421941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14631 + ... + 19310.

It is an arithmetic number, because the mean of its divisors is an integer number (3603509).

Almost surely, 2^79421940 is an apocalyptic number.

It is an amenable number.

79421940 is an abundant number, since it is smaller than the sum of its proper divisors (180030708).

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

79421940 is a wasteful number, since it uses less digits than its factorization.

79421940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33969 (or 33964 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 79421940 is about 8911.8987875761. The cubic root of 79421940 is about 429.8466011328.

The spelling of 79421940 in words is "seventy-nine million, four hundred twenty-one thousand, nine hundred forty".