1901095921 has 2 divisors, whose sum is σ = 1901095922. Its totient is φ = 1901095920.

The previous prime is 1901095897. The next prime is 1901095943. The reversal of 1901095921 is 1295901091.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1871773696 + 29322225 = 43264^2 + 5415^2 .

It is a cyclic number.

It is not a de Polignac number, because 1901095921 - 2¹³ = 1901087729 is a prime.

It is a super-2 number, since 2×1901095921² = 7228331401685676482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1901095121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 950547960 + 950547961.

It is an arithmetic number, because the mean of its divisors is an integer number (950547961).

Almost surely, 2^1901095921 is an apocalyptic number.

It is an amenable number.

1901095921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1901095921 is an equidigital number, since it uses as much as digits as its factorization.

1901095921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7290, while the sum is 37.

The square root of 1901095921 is about 43601.5586992025. The cubic root of 1901095921 is about 1238.8004183273.

The spelling of 1901095921 in words is "one billion, nine hundred one million, ninety-five thousand, nine hundred twenty-one".