290722640 has 40 divisors (see below), whose sum is σ = 727927368. Its totient is φ = 107343360.

The previous prime is 290722637. The next prime is 290722643. The reversal of 290722640 is 46227092.

It is an interprime number because it is at equal distance from previous prime (290722637) and next prime (290722643).

It can be written as a sum of positive squares in 4 ways, for example, as 33825856 + 256896784 = 5816^2 + 16028^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 290722597 and 290722606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (290722643) 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, 138731 + ... + 140810.

Almost surely, 2^290722640 is an apocalyptic number.

290722640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

290722640 is an abundant number, since it is smaller than the sum of its proper divisors (437204728).

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

290722640 is a wasteful number, since it uses less digits than its factorization.

290722640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279567 (or 279561 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 290722640 is about 17050.5906056066. The cubic root of 290722640 is about 662.4599353961.

The spelling of 290722640 in words is "two hundred ninety million, seven hundred twenty-two thousand, six hundred forty".