70637561 has 4 divisors (see below), whose sum is σ = 72916224. Its totient is φ = 68358900.

The previous prime is 70637557. The next prime is 70637563. The reversal of 70637561 is 16573607.

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: 16573607 = 2477 ⋅6691.

It is a cyclic number.

It is not a de Polignac number, because 70637561 - 2² = 70637557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70637563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1139285 + ... + 1139346.

It is an arithmetic number, because the mean of its divisors is an integer number (18229056).

Almost surely, 2^70637561 is an apocalyptic number.

It is an amenable number.

70637561 is a deficient number, since it is larger than the sum of its proper divisors (2278663).

70637561 is a wasteful number, since it uses less digits than its factorization.

70637561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2278662.

The product of its (nonzero) digits is 26460, while the sum is 35.

The square root of 70637561 is about 8404.6154581872. The cubic root of 70637561 is about 413.3759745435.

The spelling of 70637561 in words is "seventy million, six hundred thirty-seven thousand, five hundred sixty-one".