19401961 has 2 divisors, whose sum is σ = 19401962. Its totient is φ = 19401960.

The previous prime is 19401937. The next prime is 19402003. The reversal of 19401961 is 16910491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9884736 + 9517225 = 3144^2 + 3085^2 .

It is a cyclic number.

It is not a de Polignac number, because 19401961 - 2¹³ = 19393769 is a prime.

It is not a weakly prime, because it can be changed into another prime (19404961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9700980 + 9700981.

It is an arithmetic number, because the mean of its divisors is an integer number (9700981).

Almost surely, 2^19401961 is an apocalyptic number.

It is an amenable number.

19401961 is a deficient number, since it is larger than the sum of its proper divisors (1).

19401961 is an equidigital number, since it uses as much as digits as its factorization.

19401961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 19401961 is about 4404.7657145415. The cubic root of 19401961 is about 268.7087915183.

The spelling of 19401961 in words is "nineteen million, four hundred one thousand, nine hundred sixty-one".