10721890 has 16 divisors (see below), whose sum is σ = 20315520. Its totient is φ = 4062960.

The previous prime is 10721881. The next prime is 10721899. The reversal of 10721890 is 9812701.

It is an interprime number because it is at equal distance from previous prime (10721881) and next prime (10721899).

It is a super-2 number, since 2×10721890² = 229917850344200, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (10721899) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 28026 + ... + 28405.

It is an arithmetic number, because the mean of its divisors is an integer number (1269720).

Almost surely, 2^10721890 is an apocalyptic number.

10721890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

10721890 is a deficient number, since it is larger than the sum of its proper divisors (9593630).

10721890 is a wasteful number, since it uses less digits than its factorization.

10721890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56457.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 10721890 is about 3274.4297213408. The cubic root of 10721890 is about 220.5077117090.

It can be divided in two parts, 10721 and 890, that added together give a palindrome (11611).

The spelling of 10721890 in words is "ten million, seven hundred twenty-one thousand, eight hundred ninety".