215490740 has 12 divisors (see below), whose sum is σ = 452530596. Its totient is φ = 86196288.

The previous prime is 215490721. The next prime is 215490787. The reversal of 215490740 is 47094512.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 143376676 + 72114064 = 11974^2 + 8492^2 .

It is a junction number, because it is equal to n+sod(n) for n = 215490697 and 215490706.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5387249 + ... + 5387288.

It is an arithmetic number, because the mean of its divisors is an integer number (37710883).

Almost surely, 2^215490740 is an apocalyptic number.

215490740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215490740 is an abundant number, since it is smaller than the sum of its proper divisors (237039856).

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

215490740 is a wasteful number, since it uses less digits than its factorization.

215490740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10774546 (or 10774544 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 215490740 is about 14679.6028556634. The cubic root of 215490740 is about 599.5280918982.

The spelling of 215490740 in words is "two hundred fifteen million, four hundred ninety thousand, seven hundred forty".