1061655421 has 4 divisors (see below), whose sum is σ = 1063818144. Its totient is φ = 1059492700.

The previous prime is 1061655409. The next prime is 1061655433. The reversal of 1061655421 is 1245561601.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1245561601 = 9431 ⋅132071.

It is an interprime number because it is at equal distance from previous prime (1061655409) and next prime (1061655433).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1061655421 is a prime.

It is a super-2 number, since 2×1061655421² = 2254224465877374482, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1061655821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1080625 + ... + 1081606.

It is an arithmetic number, because the mean of its divisors is an integer number (265954536).

Almost surely, 2^1061655421 is an apocalyptic number.

It is an amenable number.

1061655421 is a deficient number, since it is larger than the sum of its proper divisors (2162723).

1061655421 is an equidigital number, since it uses as much as digits as its factorization.

1061655421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2162722.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 1061655421 is about 32583.0541999979. The cubic root of 1061655421 is about 1020.1433288911.

The spelling of 1061655421 in words is "one billion, sixty-one million, six hundred fifty-five thousand, four hundred twenty-one".