61991007 has 8 divisors (see below), whose sum is σ = 89012784. Its totient is φ = 38148288.

The previous prime is 61990997. The next prime is 61991029. The reversal of 61991007 is 70019916.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-61991007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61991107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 794718 + ... + 794795.

It is an arithmetic number, because the mean of its divisors is an integer number (11126598).

Almost surely, 2^61991007 is an apocalyptic number.

61991007 is a deficient number, since it is larger than the sum of its proper divisors (27021777).

61991007 is a wasteful number, since it uses less digits than its factorization.

61991007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1589529.

The product of its (nonzero) digits is 3402, while the sum is 33.

The square root of 61991007 is about 7873.4367972316. The cubic root of 61991007 is about 395.7700238496.

The spelling of 61991007 in words is "sixty-one million, nine hundred ninety-one thousand, seven".