30720690 has 288 divisors, whose sum is σ = 111541248. Its totient is φ = 5702400.

The previous prime is 30720689. The next prime is 30720691. The reversal of 30720690 is 9602703.

It is an interprime number because it is at equal distance from previous prime (30720689) and next prime (30720691).

It is a super-2 number, since 2×30720690² = 1887521588152200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (30720691) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 990975 + ... + 991005.

It is an arithmetic number, because the mean of its divisors is an integer number (387296).

Almost surely, 2^30720690 is an apocalyptic number.

30720690 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 30720690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55770624).

30720690 is an abundant number, since it is smaller than the sum of its proper divisors (80820558).

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

30720690 is a wasteful number, since it uses less digits than its factorization.

30720690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 27.

The square root of 30720690 is about 5542.6248294468. The cubic root of 30720690 is about 313.1917561186.

The spelling of 30720690 in words is "thirty million, seven hundred twenty thousand, six hundred ninety".