30521861 has 2 divisors, whose sum is σ = 30521862. Its totient is φ = 30521860.

The previous prime is 30521797. The next prime is 30521879. The reversal of 30521861 is 16812503.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30459361 + 62500 = 5519^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 30521861 - 2⁶ = 30521797 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30521861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30521461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15260930 + 15260931.

It is an arithmetic number, because the mean of its divisors is an integer number (15260931).

Almost surely, 2^30521861 is an apocalyptic number.

It is an amenable number.

30521861 is a deficient number, since it is larger than the sum of its proper divisors (1).

30521861 is an equidigital number, since it uses as much as digits as its factorization.

30521861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 30521861 is about 5524.6593560146. The cubic root of 30521861 is about 312.5146181962.

It can be divided in two parts, 3052 and 1861, that added together give a cube (4913 = 17³).

The spelling of 30521861 in words is "thirty million, five hundred twenty-one thousand, eight hundred sixty-one".