61002121651 has 2 divisors, whose sum is σ = 61002121652. Its totient is φ = 61002121650.

The previous prime is 61002121603. The next prime is 61002121669. The reversal of 61002121651 is 15612120016.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61002121651 - 2²¹ = 61000024499 is a prime.

It is not a weakly prime, because it can be changed into another prime (61002121351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30501060825 + 30501060826.

It is an arithmetic number, because the mean of its divisors is an integer number (30501060826).

Almost surely, 2^61002121651 is an apocalyptic number.

61002121651 is a deficient number, since it is larger than the sum of its proper divisors (1).

61002121651 is an equidigital number, since it uses as much as digits as its factorization.

61002121651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 25.

Adding to 61002121651 its reverse (15612120016), we get a palindrome (76614241667).

The spelling of 61002121651 in words is "sixty-one billion, two million, one hundred twenty-one thousand, six hundred fifty-one".