10721540 has 24 divisors (see below), whose sum is σ = 22619520. Its totient is φ = 4268768.

The previous prime is 10721489. The next prime is 10721549. The reversal of 10721540 is 4512701.

It is a super-2 number, since 2×10721540² = 229902839943200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (10721549) 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, 3659 + ... + 5901.

It is an arithmetic number, because the mean of its divisors is an integer number (942480).

Almost surely, 2^10721540 is an apocalyptic number.

10721540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

10721540 is an abundant number, since it is smaller than the sum of its proper divisors (11897980).

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

10721540 is a wasteful number, since it uses less digits than its factorization.

10721540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2491 (or 2489 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 10721540 is about 3274.3762764838. The cubic root of 10721540 is about 220.5053123018.

The spelling of 10721540 in words is "ten million, seven hundred twenty-one thousand, five hundred forty".